Free calculators & utilities

2011 free calculators and developer utilities that run in your browser — nothing to install, nothing uploaded.

Finance & everyday

Loan & Mortgage

Monthly repayment + full amortization schedule.

Compound Interest

Savings growth — simple vs compound, with deposits.

Percent of, % change, tip, discount & tax.

Currency Converter

Live exchange rates across 30+ currencies.

Temperature, data, length, power & more.

Words, characters, reading time & keywords.

Body-mass index + your healthy weight range.

Banking & loans

Mortgage Calculator

Monthly PITI, interest & amortization.

Car payment with tax, trade-in & APR.

Amortization Schedule

Full payment table + CSV export.

Compare loans & find your break-even.

Snowball vs avalanche, side by side.

Simple Interest

Interest, principal, rate or time.

True APR from rate + fees.

Loan Affordability

How much can you borrow (DTI)?

Pay off sooner & save interest.

CD / Fixed Deposit

Maturity value & APY.

Solve PV, FV or payment.

Compare the true cost over time.

Front & back-end DTI ratios.

Target fund & time to reach it.

Business & operations

Invoice Generator

Build & print a professional invoice — tax, totals, PDF.

Margin & Markup

Profit, gross margin & markup — solved any way round.

Units & revenue to break even — with a live chart.

Sales Tax / VAT

Add, remove or isolate tax at any rate — VAT, GST.

Work Hours & Timesheet

Weekly hours, breaks, overtime & gross pay.

What a meeting really costs — with a live ticker.

QR Code Generator

Make a QR for any link or text — PNG & SVG, fully offline.

Developer & data

Format, validate & minify JSON.

Encode & decode Base64 text.

MD5, SHA-1, SHA-256 & more.

Test & debug regular expressions live.

Timestamp Converter

Unix time ⇄ human-readable date.

Random v4 UUIDs, single or in bulk.

Decode header, payload & claims — in-browser.

Encode & decode URLs and components.

Encode & decode HTML entities safely.

Shrink CSS — strip comments & whitespace.

Strip comments & whitespace from JS.

Compress HTML, keep pre/script intact.

Turn JSON arrays into spreadsheet CSV.

Parse CSV into clean JSON objects.

Convert between JSON and YAML both ways.

Beautify & minify SQL queries.

Explain cron & see the next run times.

Binary, octal, decimal, hex & any base.

Pretty-print & validate XML with indentation.

Convert XML markup to clean JSON.

Turn JSON objects into XML markup.

HTML Beautifier

Reformat & indent messy HTML cleanly.

Format CSS — indent, space & tidy rules.

Reformat & indent minified JavaScript.

HTML → Markdown

Convert HTML into clean Markdown.

.gitignore Generator

Build a .gitignore for any stack & tool.

.htaccess Generator

Redirects, rewrites & security rules.

Encode & decode Base32 text (RFC 4648).

Keyed HMAC — SHA-1/256/384/512.

Bcrypt Generator

Hash & verify passwords with bcrypt.

JSON → TypeScript

Generate TS interfaces from any JSON.

HTTP Status Codes

Searchable reference for every status code.

Network & security

Geolocation & network info for any IP.

Query A, MX, TXT & more records.

Inspect a site's TLS certificate.

Check common open ports on a host.

Subnet Calculator

CIDR, masks & usable IP ranges.

Password Generator

Strong, random, configurable passwords.

Text & writing

UPPER, lower, Title, camelCase, snake_case & more.

Placeholder text — paragraphs, sentences, lists.

Compare two texts line by line — added & removed.

Bulk replace with case, whole-word & regex modes.

Remove Duplicates

Strip duplicate lines, keep order or sort.

Alphabetical, numeric, length, reverse or shuffle.

Turn any title into a clean URL slug.

Markdown Preview

Live Markdown → HTML, side by side.

Whitespace Remover

Trim, collapse spaces, strip blank lines.

Flip text, words or lines back to front.

Repeat any text N times, spaced or joined.

Palindrome Checker

Test if text reads the same both ways.

Translate text ⇄ Morse, with audio playback.

Binary ⇄ Text

Convert text to binary and back again.

Shift-encrypt text by any rotation.

Classic ROT13 encode / decode in one click.

Spell words as Alfa-Bravo-Charlie.

Translate English into playful Pig Latin.

Unicode fonts & styles for bios & posts.

Math & numbers

Scientific Calculator

Trig, logs, powers, memory — full keypad.

Fraction Calculator

Add, subtract, multiply & simplify fractions.

Ratio Calculator

Solve, simplify & scale ratios.

Mean, median, mode, std-dev & quartiles.

Greatest common divisor & lowest multiple.

Test primality & factorize any number.

Quadratic Solver

Roots, discriminant & vertex, with steps.

Unbiased random numbers in any range.

Convert numbers ⇄ Roman numerals.

Number to Words

Spell out numbers & money in words.

Finance & planning

Tip, total & split the bill any way.

Discount Calculator

Sale price, savings & stacked discounts.

Return on investment & annualized ROI.

Salary Converter

Hourly ⇄ annual and everything between.

Time or monthly amount to hit a goal.

Project your nest-egg to retirement.

Purchasing power over time.

Months to clear a balance & interest.

Assets minus liabilities, live.

Budget (50/30/20)

Split income into needs, wants & savings.

Health & fitness

BMR, maintenance & weight-goal calories.

US Navy method — fat & lean mass.

Four formulas + healthy BMI range.

Daily hydration target for your body.

Protein / carb / fat grams from calories.

Pregnancy due date & milestones.

Fertile window & cycle predictions.

Heart Rate Zones

Max HR & five training zones.

Pace, time or distance — solve any.

Best bedtimes & wake times by cycle.

Date & time

Exact age, next birthday & day born.

Date Difference

Days, weeks & business days between dates.

Add or count working days, skip holidays.

Countdown Timer

Live countdown to any date & time.

Add or subtract days, weeks, months, years.

Add, subtract & sum durations.

Timezone Converter

Convert times across world zones (DST-aware).

ISO week, day-of-year & quarter.

Focus / break cycles with a beep.

Stopwatch & Timer

Laps & countdown, drift-free.

Converters

°C, °F, K & Rankine, live-linked.

kg, g, lb, oz, stone, tonne & more.

km/h, mph, m/s, knots & Mach.

m², ft², acres, hectares & more.

Litres, gallons, cups, pints & more.

Cups ⇄ grams ⇄ ml, ingredient-aware.

MPG ⇄ L/100km ⇄ km/L.

Pa, bar, psi, atm, mmHg & more.

Joule, calorie, kWh, BTU & more.

US, UK, EU & cm — men, women, kids.

Color & design

HEX, RGB, HSL, HSV + tints & shades.

HEX / RGB / HSL

Convert color formats both ways.

Palette Generator

Harmony palettes from any base color.

Gradient Generator

Linear & radial CSS gradients.

Contrast Checker

WCAG AA/AAA contrast ratios.

Design CSS box-shadows visually.

Round corners & blob shapes, live.

Colorblind Simulator

See colors as CVD users do.

Color Name Finder

Nearest CSS color name ⇄ hex.

Image tools

Resize by pixels or % in your browser.

Image Compressor

Shrink JPEG/WebP file size, keep quality.

Image to Base64

Data-URI + HTML/CSS snippets.

Format Converter

PNG ⇄ JPEG ⇄ WebP.

Crop with a draggable selection.

Favicon Generator

All favicon sizes + HTML tags.

Color Extractor

Pull a palette from any image.

Web & SEO

Meta Tag Generator

Title, description, robots & more.

Open Graph Tags

Social share cards + live preview.

Robots.txt Generator

Crawl rules & sitemap directives.

Tag campaign URLs for analytics.

Keyword Density

Phrase frequency & density %.

Preview your Google search snippet.

Random & fun

Pick a random winner from a list.

Roll d4–d100 with modifiers.

Heads or tails, with stats.

Username Generator

Fresh handle ideas, any style.

Secure keys, tokens & strings.

Password Strength

Rate strength, entropy & crack time.

Unit converters

Bits, bytes, KB, MB, GB, TB, KiB, MiB, GiB.

Data Transfer Rate

bps, kbps, Mbps, Gbps, MB/s, GB/s.

Angle Converter

Degrees, radians, gradians, arcmin, turns.

Force Converter

Newton, kN, dyne, lbf, kgf, ozf.

Power Converter

Watt, kW, MW, hp, BTU/h.

Density Converter

kg/m³, g/cm³, lb/ft³, kg/L.

Frequency Converter

Hz, kHz, MHz, GHz, RPM.

Torque Converter

N·m, lbf·ft, lbf·in, kgf·m.

Flow Rate Converter

m³/s, L/s, L/min, m³/h, GPM.

Acceleration Converter

m/s², g-force, ft/s², gal.

Illuminance Converter

Lux, foot-candle, phot, kilolux.

Wind Speed Converter

m/s, km/h, mph, knots, ft/s.

Finance & investing

Grow a lump sum with compound interest.

Today’s worth of a future amount.

CAGR Calculator

Compound annual growth rate of an investment.

Years to double your money at any rate.

Dollar-Cost Averaging

Future value of steady monthly investing.

Profit, return % and break-even on a trade.

Yield % and annual income from dividends.

401(k) Calculator

Project retirement savings with employer match.

Down payment + loan amount on a home.

Net pay after taxes & deductions.

Weekly pay with overtime hours.

Commission Calculator

Commission + base on your sales.

Capital Gains Tax

Tax & net proceeds on a gain.

Savings rate + rough years to FI.

Real Rate of Return

Inflation-adjusted investment return.

Car Affordability

Max car price from a monthly budget.

Home Affordability

Home price you can afford (28/36 rule).

50/30/20 Budget

Split pay into needs / wants / savings.

Freelance Hourly Rate

Rate to charge to hit your income goal.

Math & geometry

Percentage Change

% increase/decrease between two numbers.

Pythagorean Theorem

Hypotenuse, area & angles of a right triangle.

Circle Calculator

Area, circumference & diameter from radius.

Slope Calculator

Slope, angle & equation from two points.

Distance Between Points

Euclidean distance & midpoint of 2 points.

Compute n! for any whole number.

Permutations & Combinations

nPr and nCr for choosing r from n.

Exponent Calculator

Raise a base to any power (bⁿ).

Logarithm Calculator

log in any base, plus ln and log₁₀.

Z-Score Calculator

Standard score from mean & std deviation.

Average / Mean / Median

Mean, median, mode & range of a list.

Rounding Calculator

Round, floor, ceil & truncate a number.

Modulo Calculator

Remainder & quotient of a ÷ n.

Scientific Notation

Convert numbers to a × 10ⁿ form.

Fraction to Decimal

Convert a fraction to decimal & %.

Decimal to Fraction

Convert a decimal to a reduced fraction.

Standard Deviation

Sample & population SD, variance, mean.

Area from base/height or 3 sides.

Cylinder Volume

Volume & surface area of a cylinder.

Volume & surface area of a sphere.

Volume & surface area of a cone.

Proportion Solver

Solve a/b = c/x for x.

Prime Factorization

Prime factors of any integer.

Percentage Error

Percent error vs a true value.

Health & body

TDEE Calculator

Total daily calories burned + cut/bulk.

Calories burned at rest (Mifflin-St Jeor).

One-Rep Max (1RM)

Estimate max lift from weight × reps.

Lean vs fat mass from body-fat %.

Waist-to-Height Ratio

WHtR health-risk indicator.

What cigarettes cost over time.

Calories Burned

Calories burned by activity & time.

Daily protein target by activity.

Waist-to-Hip Ratio

WHR + health-risk category.

Blood Alcohol (BAC)

Estimate BAC (Widmark). Educational.

Steps to Distance

Steps → distance & calories.

Body Surface Area

BSA (Mosteller & Du Bois).

Text & Unicode

Title Case Converter

Capitalize each major word in a title.

Sentence Case Converter

Capitalize the first letter of each sentence.

Bold Text Generator

𝗕𝗼𝗹𝗱 Unicode text for bios & posts.

Upside Down Text

Flip text to uʍop ǝpısdn.

Small Caps Generator

Convert text to sᴍᴀʟʟ ᴄᴀᴘs.

Remove Line Breaks

Flatten text into a single block.

Readability Score

Flesch reading ease & grade level.

Reverse Word Order

Reverse the order of words in text.

Alternating Case

aLtErNaTiNg mocking-case text.

Wide / Vaporwave Text

ｆｕｌｌｗｉｄｔｈ aesthetic text.

Strikethrough Text

C̶r̶o̶s̶s̶e̶d̶ ̶o̶u̶t̶ Unicode text.

Superscript Generator

ˢᵘᵖᵉʳˢᶜʳᶦᵖᵗ Unicode text.

Hashtag Generator

#Turn keywords into hashtags.

Word Frequency Counter

Rank the most-used words in text.

Remove Duplicate Words

Keep only the first of each word.

Zalgo Glitch Text

C̷r̴e̵e̶p̷y̸ glitch text generator.

Clap Text Generator

Put 👏 claps 👏 between 👏 words.

U̲n̲d̲e̲r̲l̲i̲n̲e̲d̲ Unicode text.

Ⓒⓘⓡⓒⓛⓔⓓ Unicode letters & numbers.

Time & date

Days Until a Date

Countdown of days to any future date.

Days Since a Date

Elapsed days since any past date.

Leap Year Checker

Is a year a leap year? + next one.

Day of the Week

What weekday is any date?

Weeks Between Dates

Weeks & days between two dates.

Months Between Dates

Months & years between two dates.

Birthday Countdown

Days to your next birthday + age.

Developer & web

Convert RGB colour to CMYK for print.

Convert hex colour to HSL & RGB.

Keep proportions when resizing.

PPI / Pixel Density

Screen pixels-per-inch & dot pitch.

Chmod Calculator

Unix permissions → octal & symbolic.

How long a file takes to download.

CSS clamp() Generator

Fluid responsive clamp() values.

Password Entropy

Entropy bits & crack-time estimate.

Bitwise Calculator

AND, OR, XOR, NOT & shifts.

Home & everyday

Electricity Cost

Appliance running cost per day/month/year.

Paint Calculator

How much paint a room needs.

Tile Calculator

Tiles needed for a floor or wall.

Fuel cost of any journey.

Unit Price Compare

Which package is the better deal?

Concrete Calculator

Concrete volume & bags for a slab.

Split a bill + tip between people.

More finance & investing

Bond YTM Calculator

Approximate yield to maturity of a bond.

Current Bond Yield

Annual coupon divided by market price.

Periodic bond coupon from rate and face value.

Bond Price Calculator

Discounted present value of a bond.

P/E Ratio Calculator

Price-to-earnings ratio from price and EPS.

Earnings per share from net income and shares.

PEG Ratio Calculator

P/E ratio divided by earnings growth rate.

Price-to-Book Ratio

Share price divided by book value per share.

Price-to-Sales Ratio

Share price divided by sales per share.

EPS divided by price, the inverse P/E.

Dividend Payout Ratio

Dividends per share as a share of EPS.

Dividend Growth Model

Gordon model stock valuation from dividends.

DRIP Calculator

Dividend reinvestment growth over time.

Expense Ratio Impact

Fee drag on investment growth over time.

Mutual Fund Fees

Total load and expense-ratio fees over time.

Purchasing Power

Inflation-adjusted future value of money.

Nest egg needed to retire early.

Coast FIRE Calculator

Invest now, coast to your FIRE goal.

Withdrawal Rate

Withdrawal rate vs the 4% rule.

Retirement Income

Sustainable income a nest egg provides.

Periodic payment from an immediate annuity.

Perpetuity Value

Present value of an endless cash stream.

Net present value of equal cash flows.

Internal rate of return of equal cash flows.

Time to recoup an investment’s cost.

Profitability Index

PV of inflows per dollar invested.

Risk-adjusted return above the risk-free rate.

CAPM Expected Return

Expected return from beta and market premium.

WACC Calculator

Weighted average cost of capital.

Portfolio Return

Weighted average return of a portfolio.

Asset Allocation by Age

Stock/bond split from your age.

Effective Annual Rate

EAR from a nominal rate and compounding.

Annual percentage yield from APR.

Cap Rate Calculator

NOI divided by property price.

Rental Yield Calculator

Gross and net yield of a rental property.

Cash-on-Cash Return

Annual cash flow over cash invested.

Add or remove VAT at any rate.

Add or remove GST at any rate.

Service Charge Calculator

Add a service charge and split a bill.

Gross to Net Price

Convert gross price to net price.

Markup Calculator

Cost plus markup to selling price.

Profit Margin Calculator

Profit, margin % and markup % from cost.

Gross Profit Calculator

Gross profit and margin from COGS.

Cost-Plus Pricing

Price to hit a target margin.

Percent Off Calculator

Sale price after a % discount.

Double Discount Calculator

Stack two discounts on one price.

Contribution Margin

Margin per unit and CM ratio.

Break-Even Units

Units to sell to cover fixed costs.

ROAS Calculator

Return on ad spend ratio and %.

Cost per 1,000 impressions.

Cost per click from spend and clicks.

Customer acquisition cost.

Lifetime value vs acquisition cost.

Loan-to-Value Calculator

LTV ratio and equity from loan & value.

DSCR Calculator

Debt service coverage ratio.

Working Capital

Assets minus current liabilities.

Assets over current liabilities.

Acid-test liquidity ratio.

Invoice Total Calculator

Subtotal, discount, tax and shipping.

Late Payment Fee

Interest and fee on overdue invoices.

Time and a Half

1.5x overtime rate and pay.

Day Rate Calculator

Annual income to a daily rate.

Payroll Tax Estimate

Net pay from gross, tax and deductions.

Currency Triangulation

Cross rate from two given rates.

Price Per Sq Ft

Price per square foot and metre.

Rent Affordability

Affordable rent from your income.

Security Deposit

Deposit and move-in cost from rent.

Per Diem Calculator

Meals and lodging over trip days.

Mileage Reimbursement

Miles times your per-mile rate.

Straight-Line Depreciation

Even annual depreciation of an asset.

Declining Balance Depreciation

Accelerated depreciation year one.

EBITDA as a percent of revenue.

Car Lease Payment

Monthly lease from cap cost and money factor.

Lease vs Buy a Car

Compare leasing against buying and reselling.

EV Charging Cost

Cost to charge from battery size and price.

Annual electric vs gasoline fuel cost.

Car Depreciation

Future value from an annual loss rate.

Cost of Ownership

Depreciation, fuel, insurance and upkeep.

Car Loan vs Cash

Loan interest vs investing the cash.

Trade-In Equity

Trade-in value minus loan payoff.

Total tolls for a one-way or round trip.

Fuel Economy Savings

Yearly savings from a better MPG.

Fuel wasted idling per year.

Oil Change Cost

Annual oil change cost and cost per mile.

Road Trip Fuel Stops

Fuel stops and cost for a long drive.

Net Income Calculator

Revenue minus costs, interest and taxes.

Retained Earnings Calculator

Beginning balance plus profit minus dividends.

Inventory Turnover Calculator

COGS divided by average inventory.

Average days to collect receivables.

Average days inventory is held.

Cash Conversion Cycle Calculator

DIO plus DSO minus DPO.

COGS Calculator

Beginning inventory plus purchases minus ending.

Operating Margin Calculator

Operating income divided by revenue.

Operating Income Calculator

Revenue minus COGS and operating expenses.

Burn Rate Calculator

Monthly net cash spend of a startup.

Startup Runway Calculator

Months of cash left at current burn.

Customer Lifetime Value Calculator

ARPU times gross margin over churn.

Churn Rate Calculator

Customers lost divided by customers at start.

Customers times average monthly revenue.

Monthly recurring revenue times twelve.

ARPU Calculator

Total revenue divided by active users.

Net Revenue Retention Calculator

Revenue kept from existing customers.

SaaS Magic Number Calculator

New ARR per dollar of sales spend.

Rule of 40 Calculator

Growth rate plus profit margin vs 40%.

Business Quick Ratio Calculator

Liquid assets over current liabilities.

Accounts Payable Days Calculator

Average days to pay suppliers.

Gross Revenue Calculator

Units times price, less returns and discounts.

Net Profit Margin Calculator

Net income divided by revenue.

Return on Assets Calculator

Net income divided by total assets.

Return on Equity Calculator

Net income divided by shareholder equity.

Asset Turnover Calculator

Revenue divided by average total assets.

Times Interest Earned Calculator

EBIT divided by interest expense.

Optimal order quantity to minimize cost.

Safety Stock Calculator

Buffer stock against demand variability.

Reorder Point Calculator

Lead-time demand plus safety stock.

Contribution Margin Ratio Calculator

Sales minus variable costs over sales.

Price Elasticity Calculator

Demand response to a price change.

Cost Per Acquisition Calculator

Marketing spend divided by conversions.

CAC Payback Period Calculator

Months to recover customer acquisition cost.

LTV to CAC Ratio Calculator

Lifetime value divided by acquisition cost.

Gross Revenue Retention Calculator

Revenue kept before expansion, over start.

Crypto Profit Calculator

Profit or loss from a crypto trade.

Crypto DCA Calculator

Total invested across recurring crypto buys.

Crypto Average Cost Calculator

Weighted average price of two crypto buys.

Crypto ROI Calculator

Return on investment for a crypto holding.

Crypto Capital Gains Calculator

Gain, tax and after-tax profit on a sale.

Crypto Compound Calculator

Compounded crypto growth over years.

Mining Profitability Calculator

Daily mining profit from hash rate and power.

Mining Break-Even Calculator

Days to pay off mining hardware.

Hash Rate Share Calculator

Network share and expected coins per day.

Staking Rewards Calculator

Rewards earned from staking crypto.

Staking vs Holding Calculator

Extra tokens from staking versus holding.

DeFi APY Calculator

Convert APR to APY with compounding.

Yield Farming Return Calculator

Rewards from a liquidity pool over time.

Impermanent Loss Calculator

Loss versus holding from LP price divergence.

Gas Fee Cost Calculator

Ethereum gas fee in ETH and USD.

Wei Gwei ETH Converter

Convert wei, gwei and ether units.

Satoshi to BTC Converter

Convert satoshis, bits, mBTC and BTC.

Crypto Market Cap Calculator

Market cap and FDV from price and supply.

Token Price Target Calculator

Implied price from a target market cap.

Liquidation Price Calculator

Liquidation price for leveraged trades.

Margin Call Price Calculator

Margin-call price from equity and margin.

Funding Rate Cost Calculator

Perpetual futures funding paid over time.

NFT Royalty Calculator

Royalty, fee and net on an NFT sale.

Airdrop Value Calculator

Net value of a crypto airdrop.

Crypto Allocation Calculator

Percentage weights across crypto assets.

Crypto Rebalance Calculator

Buy/sell amount to hit a target allocation.

Pip Value Calculator

Value of a pip for a forex position.

Position Size Calculator

Units to trade for a fixed risk amount.

Risk Reward Ratio Calculator

Risk/reward and break-even win rate.

Stop Loss Price Calculator

Stop-loss price and loss at the stop.

Take Profit Price Calculator

Take-profit price and profit at target.

Crypto Break-Even Price Calculator

Sell price to break even after fees.

Trading Fee Impact Calculator

Total fees from repeated round-trip trades.

Crypto Loan LTV Calculator

LTV and liquidation buffer on a crypto loan.

Halving Supply Calculator

Block reward and supply after halvings.

Token Vesting Calculator

Vested and locked tokens over a schedule.

DIME Life Insurance Need

Debt, Income, Mortgage and Education total.

Term Life Estimate

Income multiple plus expenses less assets.

Human Life Value

Present value of future net earnings.

Auto Insurance Estimate

Base rate times risk factor less discounts.

Home Insurance Estimate

Coverage times rate per $1,000 less discounts.

Health Plan Total Cost

Premiums plus your capped medical share.

Deductible vs Premium

Which plan costs less at your claim level.

Out-of-Pocket Max Reach

Bills needed to hit your OOP maximum.

Contribution growth and yearly tax savings.

Tax-free HSA vs taxable account value.

Tax saved on pre-tax FSA contributions.

Yearly copays for visits and prescriptions.

Coinsurance Share

Your share after deductible and coinsurance.

Disability Insurance Need

Monthly benefit gap versus your expenses.

Umbrella Coverage Need

Assets and income at risk beyond your limits.

Home Replacement Cost

Square footage times build cost per sq ft.

Actual Cash Value

Replacement cost less age depreciation.

Premium Proration

Earned premium and refund for partial terms.

No-Claim Discount

Net premium after a no-claim bonus.

Level payout from principal over N years.

Pension Lump vs Annuity

Present value of payments versus a lump sum.

Benefit Claiming Adjustment

Adjust a benefit for early or late claiming.

Full premium plus the admin fee.

Workers Comp Premium

Payroll times rate times experience mod.

Liability Limit Need

Cover net worth plus an income buffer.

Gap Insurance Need

Loan balance minus vehicle actual cash value.

Pet Insurance Value

Reimbursed vet costs versus the premium.

Renters Coverage Need

Sum of belongings plus a safety buffer.

Whole vs Term Cost

Lifetime premiums and the invested difference.

Self-Insurance Fund

Monthly savings to reach a reserve target.

Deductible Break-Even

Claim-free years to cover a higher deductible.

Inflation Rider

Future coverage needed after inflation.

Cash Value Life

Projected cash value from premiums and rate.

Mortgage Protection

Payoff balance plus a payment buffer.

Income Replacement

Present value of income with growth.

Emergency Medical Fund

Out-of-pocket max per person plus a buffer.

Click-Through Rate Calculator

CTR from clicks and impressions.

Cost Per Lead Calculator

CPL from spend and leads generated.

Cost Per Mille Calculator

Cost per 1,000 ad impressions.

Engagement Rate Calculator

Engagement rate by follower count.

Follower Growth Rate Calculator

Growth rate from start to end count.

Reach vs Impressions Calculator

Average frequency from reach & impressions.

Email Open Rate Calculator

Open rate from opens and deliveries.

Email Click Rate Calculator

CTR and click-to-open rate for email.

Bounce Rate Calculator

Bounce rate from bounces and sessions.

Average Order Value Calculator

AOV from revenue and order count.

Cart Abandonment Rate Calculator

Abandonment from carts vs purchases.

Return On Ad Spend Calculator

ROAS from revenue and ad spend.

Ad Budget Allocation Calculator

Split ad budget across channels.

Funnel Conversion Calculator

Stage rates from visitors to customers.

Lead to Customer Rate Calculator

Close rate from leads to customers.

Marketing ROI Calculator

ROI from marketing revenue and cost.

YouTube Ad Revenue Calculator

Estimated revenue from views and RPM.

Influencer Cost Per Post Calculator

CPM and cost per engagement of a post.

Net Promoter Score Calculator

NPS from promoters and detractors.

Viral Coefficient Calculator

K-factor from invites and conversion.

Share of Voice Calculator

Brand share of total market activity.

Cost Per View Calculator

CPV from spend and video views.

Cost Per Engagement Calculator

CPE from spend and engagements.

Blended CAC Calculator

CAC from total spend and new customers.

Conversion Value Calculator

Total value and ROI of conversions.

Target ROAS Calculator

Required ROAS for a revenue goal.

Break-Even ROAS Calculator

Minimum ROAS from profit margin.

CAC Payback Period Calculator

Months to recoup acquisition cost.

Email List Growth Rate Calculator

Net list growth from subs and unsubs.

Webinar Conversion Calculator

Attendance and buyer conversion rates.

Landing Page Conversion Calculator

Conversion rate from visitors.

Social Post Frequency Calculator

Posts per day, week and month.

Baby First-Year Cost

Total cost of baby’s first year.

Monthly Diaper Cost

Daily, monthly and yearly diaper spend.

Formula Feeding Cost

Daily, monthly and yearly formula cost.

529 College Savings

Project a college fund’s future value.

Cost of Raising a Child

Total cost to raise a child to 18.

Allowance by Age

Kids’ allowance by age of child.

Baby Shower Budget

Plan the cost of a baby shower.

Maternity Leave Pay

Total pay during maternity leave.

Yearly and monthly daycare costs.

Babysitter Cost

Cost of a babysitter for the night.

First-year cost of raising twins.

Child Support Estimate

Rough support as a share of income.

Zero-Based Budget

Assign every dollar until you reach zero.

Envelope Budget

Split income into cash spending envelopes.

Paycheck Budget Split

Split a paycheck into needs, wants, savings.

Smallest balance first payoff plan.

Highest APR first payoff plan.

Card Minimum Payoff

True cost of paying only the minimum.

Credit Utilization

Balance-to-limit ratio and score impact.

Rent-to-Income Ratio

Is your rent within the 30% rule?

Weekly and monthly food budget by household.

Subscription Cost

Yearly and 5-year cost of subscriptions.

Subscription Break-Even

When a subscription beats pay-per-use.

Allowance Savings

How saved allowance grows over the years.

Monthly amount to reach a dated goal.

Pay Raise Impact

New salary and increase from a raise.

COLA Adjustment

Does your raise keep up with inflation?

Salary After Tax

Quick net pay from gross salary.

Portfolio for a frugal early retirement.

Portfolio for a high-spending early retirement.

Portfolio when part-time income helps.

Savings Rate to Retire

Years to FI from your savings rate.

Spending Cut Impact

Invested value of a monthly spending cut.

Future value of a small daily spend.

No-Spend Challenge

Savings from a no-spend streak.

Cash Back Value

Cash back earned from card spending.

Rewards Points Value

Dollar value of loyalty points.

Annual vs Monthly

Savings from paying annually vs monthly.

Net cost divided by number of uses.

Clothing cost divided by times worn.

Gym Cost Per Visit

Membership fee divided by visits.

Savings from brewing coffee at home.

Quit Smoking Savings

Money saved by giving up cigarettes.

Side Hustle Goal

Weeks of side work to hit a goal.

Hourly Freedom Number

Hours worked to cover monthly expenses.

Passive income as a share of expenses.

Years of expenses your net worth covers.

Money Ratios by Age

Savings benchmarks by age vs income.

Closing Costs Calculator

Down payment, closing fees, cash to close.

Down Payment Savings

Time to save your home down payment.

Private mortgage insurance monthly cost.

Property Tax Calculator

Annual and monthly property tax estimate.

HOA Impact Calculator

Long-term cost of monthly HOA dues.

Early Payoff Calculator

Interest saved with extra monthly payments.

Biweekly Mortgage

Savings from biweekly mortgage payments.

HELOC Payment Calculator

Interest-only and amortized HELOC payments.

Home Equity Calculator

Equity, LTV, and borrowable amount.

Mortgage Points Calculator

Cost and break-even of buying rate points.

Rent Increase Calculator

Projected rent after annual increases.

Rental net operating income from income and expenses.

Price-to-Rent Ratio

Buy vs rent price-to-rent ratio.

Profit and ROI on a fix-and-flip.

Rehab Budget Calculator

Renovation budget with contingency buffer.

Vacancy Loss Calculator

Annual income lost to vacant days.

Rental Cash Flow

Monthly cash flow after all expenses.

Seller Net Proceeds

Cash netted after selling a home.

Rent Proration Calculator

Prorated rent for a partial month.

Mortgage Recast Calculator

New payment after a lump-sum recast.

PITI Payment Calculator

Principal, interest, taxes, insurance payment.

Debt Yield Calculator

NOI divided by loan amount.

Loan Constant Calculator

Annual mortgage constant from rate and term.

Gross Rent Multiplier

Price divided by annual gross rent.

One Percent Rule

Rent vs 1% of purchase price.

Fifty Percent Rule

Estimated expenses and cash flow at 50%.

Break-Even Occupancy

Occupancy needed to cover costs and debt.

Home Appreciation

Future home value from annual appreciation.

Cash Reserve Calculator

Months of housing costs to keep in reserve.

Land Value Calculator

Land vs building value split.

Rent-to-Income Ratio

Rent as a share of gross income.

Mortgage vs Invest

Prepay mortgage vs invest the difference.

Closing Tax Proration

Prorate property taxes at closing.

Refinance Break-Even

Months to recoup refinance closing costs.

Interest-Only Mortgage

IO payment vs payment after the IO period.

Escrow Payment Calculator

Monthly escrow for taxes and insurance.

Trip Budget Calculator

Flights, hotel, food and extras totalled.

Points Value Calculator

Miles and points worth in cash.

Baggage Fee Calculator

Checked-bag fees across passengers and legs.

Travel Cash Needed

Daily budget and rate to foreign cash.

Tip Abroad Calculator

Local-currency tip and bill split.

Vacation Savings

Monthly saving to hit a trip goal.

Hotel Cost Calculator

Nightly rate, nights, rooms and tax.

Rental Car Cost

Daily rate, insurance and fees totalled.

Gas vs Flight Cost

Driving fuel cost versus airfare.

Flight Carbon Offset

Flight CO2 and cost to offset.

Miles to Next Tier

Miles and trips to the next status tier.

Travel Insurance Estimate

Trip cost and rate to premium estimate.

More math & geometry

Greatest common divisor of two integers.

Least common multiple of two integers.

Cube Root Calculator

Cube root of any number, negatives too.

Nth Root Calculator

Any-index real root of a number.

Natural Log Calculator

ln(x) plus log base 10 and 2.

Absolute Value Calculator

Magnitude of any positive or negative number.

Reciprocal Calculator

Multiplicative inverse 1/n of a number.

Cross Multiplication

Solve a/b = c/d for the unknown term.

Significant Figures

Round a number to n significant figures.

Mixed to Improper

Mixed number to improper fraction converter.

Improper to Mixed

Improper fraction to mixed number converter.

Fraction Simplifier

Reduce a fraction to lowest terms.

Arithmetic Sequence

Nth term and sum of an arithmetic series.

Geometric Sequence

Nth term and sum of a geometric series.

Fibonacci Calculator

Nth Fibonacci number and the sequence.

Triangular Number

Nth triangular number, n(n+1)/2.

Sum of all whole numbers 1 through n.

Factorial Trailing Zeros

Trailing zeros of n! via powers of 5.

Perfect Square Checker

Is a number a perfect square?

Perfect Number Checker

Does a number equal its divisor sum?

Collatz Calculator

Steps to reach 1 in the 3n+1 problem.

Digit Sum Calculator

Sum of digits and digital root.

Divisor Counter

Count and list all divisors of a number.

GCD of a comma-separated list of integers.

LCM of a comma-separated list of integers.

Square Root Calculator

Square root of any number, negatives too.

Divisibility Checker

Is a divisible by b? Quotient and remainder.

Coprime Checker

Are two integers relatively prime?

Nth Prime Calculator

The prime number at position n.

Prime Number Generator

All primes up to a chosen limit.

Sum of Divisors

Sigma and aliquot sum of a number.

Factor Pairs Calculator

All factor pairs that multiply to n.

Modular Exponentiation

Compute (a^b) mod m by fast squaring.

Modular Inverse

Multiplicative inverse of a modulo m.

Discriminant Calculator

b² − 4ac and the nature of the roots.

Sum of squares 1² through n².

Circle Area Calculator

Area of a circle from radius.

Circle Circumference Calculator

Perimeter of a circle from radius.

Equilateral Triangle Calculator

Area, height and perimeter from side.

Right Triangle Calculator

Hypotenuse, area and angles from legs.

Hypotenuse Calculator

Longest side of a right triangle.

Rectangle Area Calculator

Area, perimeter and diagonal.

Square Area Calculator

Area, perimeter and diagonal from side.

Trapezoid Area Calculator

Area from parallel sides and height.

Parallelogram Area Calculator

Area from base and height.

Rhombus Area Calculator

Area from the two diagonals.

Regular Polygon Area Calculator

Area of a regular n-gon.

Ellipse Area Calculator

Area from the two semi-axes.

Sphere Surface Area Calculator

Surface area from radius.

Cube Volume Calculator

Volume, surface area and diagonal.

Rectangular Prism Volume Calculator

Volume and surface area of a cuboid.

Pyramid Volume Calculator

Volume from base area and height.

Torus Volume Calculator

Volume and surface area of a donut.

Sector Area Calculator

Area and arc length of a sector.

Arc Length Calculator

Arc length from radius and angle.

Chord Length Calculator

Chord from radius and central angle.

Midpoint Calculator

Midpoint between two (x, y) points.

Line Equation Calculator

y = mx + b from two points.

Law of Cosines Calculator

Third side from two sides and angle.

Law of Sines Calculator

Unknown side from a side and two angles.

Degrees Radians Calculator

Convert angles degrees to radians.

Radius from Area Calculator

Circle radius from a known area.

Mean Median Mode Calculator

Averages of a data set.

Variance Calculator

Sample or population variance.

Percentile Calculator

Value at the nth percentile.

Range Calculator

Min, max and range of a data set.

Coefficient of Variation Calculator

Std deviation relative to the mean.

Geometric Mean Calculator

Nth root of the product of values.

Harmonic Mean Calculator

Reciprocal average of values.

Weighted Average Calculator

Weighted mean of values and weights.

Quartiles & IQR Calculator

Q1, Q2, Q3 and interquartile range.

Confidence Interval Calculator

Interval for a mean with margin of error.

Weight on Other Planets

Your weight across the solar system.

Age on Other Planets

Your age in every planet year.

Planet Weight Converter

Convert weight between any two worlds.

Orbital Period Calculator

Kepler's third law period from orbit size.

Light Travel Time

How long light takes to arrive.

Light-Year Converter

Light-years to km, miles, AU, parsecs.

Parsec Converter

Parsecs to light-years, AU and km.

Telescope Magnification

Magnification from focal lengths.

Focal Ratio Calculator

Telescope f-ratio from focal length.

Field of View Calculator

True field of view through the eyepiece.

Angular Size Calculator

Apparent size from object size and distance.

Apparent Magnitude

Observed brightness from distance modulus.

Absolute Magnitude

Intrinsic brightness from apparent magnitude.

Redshift Velocity

Recession velocity from redshift z.

Tsiolkovsky delta-v from mass ratio.

Surface Gravity

Planet gravity from mass and radius.

Alignment period of two orbits.

Julian Date Converter

Calendar date to Julian Date.

GMST and local sidereal time.

Zodiac Sign Finder

Star sign from a birth date.

Astronomical Unit Converter

AU to km, miles and light units.

Schwarzschild Radius

Black hole event horizon radius.

Tidal Force Calculator

Tidal stretching near a massive body.

Goldilocks zone from star luminosity.

Hohmann Transfer

Transfer delta-v and travel time.

Gravitational Time Dilation

Clock slowdown near a mass.

Star Luminosity

Luminosity from radius and temperature.

Black Hole Temperature

Hawking temperature from mass.

Orbital Eccentricity

Eccentricity from periapsis and apoapsis.

Planetary Density

Mean density from mass and radius.

Tidal breakup distance for a satellite.

Exoplanet Transit Depth

Starlight dip from a transiting planet.

Moon Weight Calculator

Your weight on the lunar surface.

Solar Irradiance

Sunlight intensity by distance from the Sun.

Kardashev Scale

Civilisation type from power output.

Redshift Distance

Galaxy distance from redshift via Hubble law.

Estimate acceleration from horsepower and weight.

Horsepower from Torque

HP = torque x RPM / 5252.

Torque from Horsepower

Torque = HP x 5252 / RPM.

Engine Displacement

Litres, cc and ci from bore and stroke.

Compression Ratio

(swept + clearance) / clearance volume.

Quarter Mile ET

ET and trap speed from hp and weight.

Speedometer Error

True speed after a tire size change.

Range from battery size and mi/kWh.

CC to Horsepower

Estimate hp from displacement in cc.

AFR and lambda from air and fuel mass.

Tire Diameter Speed

Speed from tire diameter and wheel RPM.

Gear Ratio Speed

Speed from RPM, gearing and tire size.

Final Drive Ratio

Ring gear teeth / pinion gear teeth.

Fuel Injector Size

cc/min and lb/hr from hp and BSFC.

Boost Horsepower

Boosted hp from NA power and psi.

Backspacing from wheel width and offset.

Braking Distance

Stopping distance from speed and grip.

Hydroplane Speed

Hydroplaning speed from tire pressure.

EV mi/kWh into MPGe equivalent.

Kilometers Per Liter

km/L, L/100km and MPG from a fill-up.

Antifreeze and water for a target ratio.

CCA and cold cranking from amp-hours.

Alternator Output

Load current vs alternator amps.

Molarity Calculator

Molar concentration from moles and litres.

Molality Calculator

Moles of solute per kg of solvent.

Molar Mass Calculator

Grams per mole from mass and moles.

Solution Dilution

C1V1 = C2V2 dilution solver.

Actual over theoretical yield, as a percent.

Convert moles into a mass in grams.

Convert a mass in grams into moles.

Moles into particle count via Avogadro.

PV = nRT solved for moles.

P1V1 = P2V2 at constant temperature.

V1/T1 = V2/T2 at constant pressure.

Gay-Lussac's Law

P1/T1 = P2/T2 at constant volume.

Combined Gas Law

P1V1/T1 = P2V2/T2 solved for V2.

pH from Concentration

pH = -log10[H+] with pOH too.

pOH = -log10[OH-] with pH too.

pKa = -log10(Ka) acid strength.

Henderson-Hasselbalch

Buffer pH from pKa and A-/HA ratio.

Percent Composition

Mass of element over total compound mass.

Empirical Formula

Simplest mole ratio of two elements.

PPM Concentration

Parts per million from mass ratio.

Solute mass over solution mass, percent.

Solute volume over solution volume, percent.

Normality Calculator

Normality from molarity and valence.

Equivalent Weight

Molar mass divided by the n-factor.

Titration Calculator

Unknown concentration via M1V1 = M2V2.

Radioactive Half-Life

Remaining amount after decay over time.

Gibbs Free Energy

ΔG = ΔH - TΔS spontaneity check.

Reaction Enthalpy

ΔH from products minus reactants.

Molar Volume of Gas

Gas volume from V = nRT/P.

Freezing Point Depression

ΔTf = i·Kf·molality.

Boiling Point Elevation

ΔTb = i·Kb·molality.

Osmotic Pressure

Π = iMRT in atmospheres.

Change in concentration over time.

Desired product mass over reactant mass.

Theoretical Yield

Max product mass from limiting reagent.

Avogadro Number

Particles into moles via Avogadro.

Weighted GPA Calculator

Honors and AP bonus points on your GPA.

Cumulative GPA Calculator

Combine prior and current term GPAs.

Semester GPA Calculator

Letter grades and credits to a 4.0 GPA.

Percentage to GPA

Percentage grade to a 4.0 GPA point.

Letter Grade to GPA

A+ to F converted to 4.0 GPA points.

Class Rank Percentile

Rank and class size to a percentile.

Credit Hours Needed

Credits required to hit a target GPA.

Study Time Planner

Weekly study hours from your credit load.

Days and study hours until your exam.

Reading Speed Calculator

Words read and time to words per minute.

Typing Speed WPM

Characters, time and errors to typing WPM.

Word count to estimated page count.

Page count to estimated word count.

Essay Word Target

Word target and words left for an essay.

Attendance Percentage

Classes attended versus total as a percentage.

Weighted Category Grade

Homework, quiz and exam weights to a grade.

Curved Grade Calculator

Scale a raw score using a grading curve.

Score Needed to Pass

Final score needed to reach a passing grade.

Points to Percentage

Points earned out of total to a percentage.

Percentage to Letter Grade

Percentage score to a letter grade.

Check your GPA against honor roll tiers.

Dean's List Calculator

Check GPA and credits for Dean's List.

Best section scores across SAT attempts.

ACT Composite Score

Four ACT sections to a composite score.

Grade Average Calculator

Average a list of numeric grades.

Final Grade Projector

Current grade and final score to a course grade.

Rubric Score Calculator

Sum rubric criteria into a percentage.

Scaled Test Score

Raw score to a scaled score range.

Percentile to Score

Percentile to a score via mean and SD.

Study Break Ratio

Focus and break cycles for a study session.

Class Retention Rate

Students retained versus started as a rate.

Quiz Average Calculator

Average quiz scores, drop lowest optional.

Velocity Calculator

Speed from distance and time.

Average Velocity Calculator

Displacement over elapsed time.

Force Calculator

Force from mass and acceleration.

Kinetic Energy Calculator

Energy of a moving mass.

Potential Energy Calculator

Stored energy at a height.

Work Done Calculator

Force applied over a distance.

Mechanical Power Calculator

Work performed per unit time.

Projectile Motion Calculator

Range, height and flight time.

Free Fall Calculator

Distance and speed while falling.

Terminal Velocity Calculator

Max falling speed with air drag.

Friction Force Calculator

Force from friction coefficient.

Hooke’s Law Calculator

Spring force from stretch.

Pendulum Period Calculator

Swing time from length.

Centripetal Force Calculator

Inward force in circular motion.

Centripetal Acceleration

Inward acceleration in a circle.

Moment of Inertia Calculator

Rotational inertia of shapes.

Gravitational Force Calculator

Attraction between two masses.

Escape Velocity Calculator

Speed to escape gravity.

Orbital Velocity Calculator

Speed for a circular orbit.

Buoyancy Force Calculator

Upthrust on a submerged object.

Elastic Collision Calculator

Velocities after elastic impact.

Inelastic Collision Calculator

Combined velocity after impact.

Impulse Momentum Calculator

Impulse from force and time.

RPM to Linear Speed

Surface speed from rotation.

Gear Ratio Calculator

Ratio from gear tooth counts.

Mechanical Advantage

Load force over effort force.

Machine Efficiency Calculator

Output over input energy.

Newton’s Second Law

Acceleration from net force.

Weight from Mass Calculator

Weight from mass and gravity.

Displacement Calculator

Distance under acceleration.

Acceleration Calculator

From velocity change and time.

Tension Force Calculator

Rope tension on a mass.

Normal Force Calculator

Support force on a surface.

Inclined Plane Calculator

Ramp forces and acceleration.

Pulley System Calculator

Effort from rope segments.

Torque Lever Calculator

Torque from force and lever arm.

Wave Speed Calculator

Speed from frequency and wavelength (v=fλ).

Period & Frequency

Period and angular frequency from frequency.

Observed frequency shift for moving sources.

Angle of refraction from indices of refraction.

Thin Lens Equation

Image distance and magnification (1/f=1/do+1/di).

Image Magnification

Magnification and image height (m=-di/do).

Mirror Equation

Focal length, image distance and magnification.

Energy in joules and eV (E=hc/λ).

Intensity to Decibels

Sound level in dB from intensity (W/m²).

Sound Attenuation

Level drop with distance (inverse-square).

Refractive Index

Index of refraction from light speed (n=c/v).

Diffraction Grating

Diffraction angle from lines/mm and order.

Harmonic frequency and wavelength (fn=nv/2L).

String Frequency

Fundamental pitch from tension and density.

Beats from two tone frequencies (|f1−f2|).

Decibel Addition

Sum two dB levels logarithmically.

Linear Expansion

Length change from heating (ΔL=αL₀ΔT).

Volume Expansion

Volume change from heating (ΔV=βV₀ΔT).

Energy to change temperature (Q=mcΔT).

Latent Heat of Fusion

Energy to melt a mass (Q=mL).

Heat Conduction

Conduction rate through a slab (Fourier).

Stefan-Boltzmann Law

Radiated power from temperature (P=εσAT⁴).

Carnot Efficiency

Max engine efficiency (η=1−Tc/Th).

Feels-like temperature (NWS formula).

Feels-like temperature from heat and humidity.

Dew point from temperature and humidity.

Relative Humidity

Humidity from temperature and dew point.

Wet-Bulb Temperature

Wet-bulb temp from heat and humidity (Stull).

R-Value Insulation

Insulation R-value and U-value (R=d/k).

Thermal Resistance

Conductive resistance in K/W (R=L/kA).

Blackbody Peak Wavelength

Peak wavelength from temperature (Wien).

Specific Heat Capacity

Specific heat from Q, mass and ΔT.

Coefficient of Performance

Ideal COP for cooling and heating (Carnot).

Pressure Altitude

Pressure altitude from altimeter setting.

Speed of Sound in Air

Sound speed in dry air by temperature.

Total internal reflection angle (θc=asin n₂/n₁).

Betting Odds Converter

American to decimal, fractional, implied.

American to Decimal

Moneyline odds to decimal odds.

Decimal to Fractional

Decimal odds to fractional and more.

Implied Probability

Break-even probability from odds.

Combined odds and payout of a parlay.

Kelly Criterion

Optimal bet size from odds and edge.

Expected Value Bet

EV of a wager from odds and edge.

One-Sample Z-Test

Z statistic and two-tailed p-value.

Two-Sample T-Test

Pooled t statistic, df and p-value.

Chi-Square Test

Goodness-of-fit chi-square and p-value.

Z-score to left, right or two-tailed p.

Correlation Coefficient

Pearson r between two data sets.

Linear Regression

Least-squares slope, intercept and R².

R-Squared Calculator

R² and variance explained from r.

Standard Error (SEM)

Standard error of the mean, s/√n.

A/B Test Significance

Two-proportion z-test for A vs B.

Conversion Rate Lift

Absolute and relative lift between rates.

Poisson Probability

P(X=k) and cumulative Poisson values.

Binomial Probability

Exact and cumulative binomial probabilities.

Normal Probability

Area under a normal curve between bounds.

Percentile Rank

Percentile rank of a score in data.

Outlier Detection

IQR method with 1.5×IQR fences.

Covariance Calculator

Sample and population covariance of X,Y.

Cohen's d Calculator

Effect size from two group summaries.

Odds Ratio Calculator

Odds ratio and 95% CI from a 2×2 table.

Relative Risk Calculator

Risk ratio and 95% CI between groups.

Sensitivity / Specificity

Sensitivity, specificity, PPV, NPV, accuracy.

Mean and variance of a discrete distribution.

Five-Number Summary

Min, Q1, median, Q3 and max.

Coefficient of Determination

R² from paired X and Y data.

Sample Size (Proportion)

Survey size for a target margin of error.

Sample Size (Mean)

Sample size to estimate a mean.

Effect Size Calculator

Cohen's d and Hedges' g from two samples.

Z-score and percentile of a value.

Midrange Calculator

Average of the min and max values.

Robust mean after trimming both tails.

Mean Absolute Deviation

Average absolute distance from the mean.

Root Mean Square

Quadratic mean of a data set.

Geometric Std Deviation

Multiplicative spread of positive data.

Prediction Interval

Interval for one future observation.

Tolerance Interval

Normal two-sided tolerance interval.

Signal-to-Noise Ratio

Mean over standard deviation, plus dB.

At Least One Probability

Chance an event occurs in n trials.

More converters

Cooking Volume Converter

Cups, tbsp, tsp, mL, fl oz, pints.

Cooking Weight Converter

Grams, oz, lb, cups of flour or sugar.

Butter Converter

Sticks, tbsp, cups, grams and ounces.

Water Hardness Converter

ppm, gpg, dH, fH, mmol/L, mEq/L.

Typography Unit Converter

px, pt, pica, em, rem, inch, mm.

Resolution Density Converter

DPI, PPI, dpcm, dpmm, dppx.

Cups to Grams Calculator

Cups of any ingredient to grams.

Oven Temperature Calculator

Celsius, Fahrenheit and gas mark.

Temperature Scales Calculator

Celsius, Fahrenheit, Kelvin, Rankine.

Coffee Ratio Calculator

Coffee-to-water ratio for any brew.

Print Size Calculator

Pixels and DPI to inches and cm.

Megapixel Calculator

Pixel dimensions to megapixels and ratio.

Paper Size Calculator

A-series, B-series, Letter, Legal dimensions.

Ring Size Converter

Circumference to US and EU ring size.

Hat Size Converter

Head circumference to hat size.

Clothing Size Converter

US, UK and EU dress sizes.

Glove Size Converter

Hand circumference to glove size.

Wire Gauge Converter

AWG to diameter in mm and inches.

Needle Gauge Converter

Needle gauge to outer diameter mm.

Drill Bit Size Converter

Fractional inch to mm and decimal.

Knitting Gauge Calculator

Gauge swatch to stitches and rows.

Fabric Yardage Calculator

Pieces and width to yards needed.

Map Scale Calculator

Map distance to real ground distance.

Decibel Ratio Calculator

Decibels to power and amplitude ratio.

Exposure Value Calculator

Aperture, shutter and ISO to EV.

Focal Length Equivalent

Focal length and crop factor to 35mm.

F-Stop Calculator

Focal length and f-number to aperture.

Tire Size Calculator

Tire code to diameter and circumference.

Concentration to pH, pOH and nature.

Lumens to Watts Calculator

Lumens and watts by bulb type.

Firewood Cord Calculator

Stack dimensions to cords of wood.

Luminance Converter

Nit, cd/m², stilb, lambert, foot-lambert.

Luminous Flux Converter

Lumen, millilumen, kilolumen.

Luminous Intensity Converter

Candela, mcd, kcd, candlepower.

Radiation Dose Converter

Sievert, mSv, µSv, rem, millirem.

Absorbed Dose Converter

Gray, milligray, rad, erg/gram.

Radioactivity Converter

Becquerel, MBq, GBq, curie, mCi.

Electric Charge Converter

Coulomb, mAh, Ah, faraday.

Capacitance Converter

Farad, mF, µF, nF, pF.

Inductance Converter

Henry, mH, µH, nH.

Resistance Converter

Ohm, milliohm, kilohm, megohm.

Conductance Converter

Siemens, mho, mS, µS.

Voltage Converter

Volt, millivolt, kilovolt, megavolt.

Electric Current Converter

Ampere, microamp, milliamp, kiloamp.

Magnetic Flux Converter

Weber, milliweber, maxwell, line.

Flux Density Converter

Tesla, millitesla, gauss, milligauss.

Dynamic Viscosity Converter

Pa·s, poise, centipoise, mPa·s.

Kinematic Viscosity Converter

m²/s, stokes, centistokes.

Thermal Conductivity Converter

W/m·K, BTU/hr·ft·°F, cal/s·cm·°C.

Specific Heat Converter

J/kg·K, kJ/kg·K, cal/g·°C, BTU/lb·°F.

Heat Flux Converter

W/m², BTU/hr·ft², cal/s·cm².

Catalytic Activity Converter

Katal, µkat, nkat, enzyme unit.

Mole, millimole, micromole, kilomole.

Surface Tension Converter

N/m, mN/m, dyne/cm, erg/cm².

Momentum Converter

kg·m/s, g·cm/s, lb·ft/s, slug·ft/s.

Impulse Converter

N·s, kg·m/s, lbf·s, dyne·s.

Spring Constant Converter

N/m, N/mm, lbf/in, kgf/m.

Specific Energy Converter

J/kg, kJ/kg, cal/g, BTU/lb, Wh/kg.

Entropy Converter

J/K, kJ/K, cal/K, BTU/°F.

Thermal Resistance Converter

K/W, °C/W, K/kW, °F·hr/BTU.

Elastic Modulus Converter

Pa, kPa, MPa, GPa, psi, ksi.

min/km, min/mi, sec/100m, sec/400m.

Specific Volume Converter

m³/kg, L/kg, cm³/g, ft³/lb.

Mass Flow Rate Converter

kg/s, g/s, kg/h, lb/s, t/h.

Angular Velocity Converter

rad/s, deg/s, RPM, rev/s.

Wavelength & Frequency Calculator

Convert wavelength ↔ frequency via c = fλ.

Sound Pressure Level Calculator

Convert pascals ↔ decibels (dB SPL).

Yeast Converter

Fresh, active dry and instant yeast.

Rice to Water Ratio

Water per cup by rice type.

Flight Time Calculator

Distance and speed to flight duration.

Layover Time Calculator

Gap between arrival and next departure.

Time Zone Difference

Hours between two UTC offsets.

Great Circle Distance

Haversine distance between two lat/long points.

Packing Weight Limit

Weight remaining before the allowance.

Altitude Air Pressure

Air pressure at a given altitude.

Mach Number Calculator

Speed and temperature to Mach number.

Ground Speed Calculator

Airspeed and wind to ground speed.

Crosswind Component

Wind split into cross and head parts.

Density Altitude

Pressure altitude and temp to density altitude.

True Airspeed Calculator

Indicated speed and altitude to TAS.

Fuel used and time to burn rate.

Climb Rate Calculator

Altitude gained and time to feet per minute.

Descent Rate Calculator

Altitude to lose and time to ft/min.

Distance before airport to start descent.

Holding Fuel Calculator

Burn rate and hold time to fuel used.

Flight ETA Calculator

Departure, duration and zone to arrival time.

Knots into mph, km/h and m/s.

Nautical Distance

Nautical miles into km, miles and metres.

Walking Distance Time

Distance and pace to walking time.

Driving Time Calculator

Distance, speed and stops to drive time.

Days Until Trip

Days, weeks and months between two dates.

Time at Destination

Home time plus offset to local time.

Connection Risk

Layover versus minimum connection time.

More developer tools

HTML Entity Decoder

Decode named & numeric HTML entities.

JSON String Escaper

Escape text into a JSON string literal.

JSON String Unescaper

Decode \n, \t, \uXXXX escape sequences.

Unicode Escape Converter

Text to \uXXXX escape sequences.

Unicode Unescape Converter

Decode \uXXXX Unicode escapes.

Rotate printable ASCII by 47 places.

ASCII to Hex Converter

Text to space-separated hex codes.

Hex to ASCII Converter

Hex codes back to readable text.

Text to Decimal Converter

Text to space-separated decimal codes.

Decimal to Text Converter

Decimal codes back to readable text.

String to Char Codes

String into a [code, code] array.

Char Codes to String

Array of codes back to a string.

Reverse Hex String

Swap big-endian and little-endian hex.

NanoID Generator

Random 21-char URL-safe unique IDs.

kebab-case Converter

Words joined by hyphens, lowercased.

snake_case Converter

Words joined by underscores, lowercased.

camelCase Converter

lowerFirst, capitalized rest, no spaces.

PascalCase Converter

Every word capitalized, no spaces.

CONSTANT_CASE Converter

UPPERCASE words joined by underscores.

dot.case Converter

Words joined by dots, lowercased.

Train-Case Converter

Capitalized words joined by hyphens.

path/case Converter

Words joined by slashes, lowercased.

Regex Escape Tool

Escape . * + ? and other regex chars.

Leetspeak Converter

Swap letters for lookalike leet digits.

Encode text with the Bitcoin Base58 set.

Base64URL Decoder

Decode URL-safe base64 (- and _).

Base64URL Encoder

URL-safe base64, no padding.

JSON to Query String

JSON object into a URL query string.

Query String to JSON

URL query string into a JSON object.

MD5 Hash Generator

32-char MD5 checksum of any text.

SHA-1 Hash Generator

40-char SHA-1 digest of any text.

SHA-256 Hash Generator

64-char SHA-256 digest of any text.

CRC32 Checksum Generator

8-char CRC32 checksum of any text.

Adler-32 Checksum Generator

8-char Adler-32 checksum of any text.

Break a URL into all its parts.

Unicode Code Point Lookup

Decimal, U+, entity, UTF-8 and UTF-16.

RGB to HSL Converter

Convert RGB colors to HSL and CSS.

HSL to RGB Converter

Convert HSL colors to RGB and hex.

HSL to Hex Converter

Convert HSL colors to hex codes.

RGB to HSV Converter

Convert RGB colors to HSV / HSB.

HSV to RGB Converter

Convert HSV / HSB colors to RGB and hex.

Relative Luminance

WCAG relative luminance from a hex color.

Hex Opacity Calculator

Opacity % to hex alpha and 8-digit hex.

Lighten / Darken Color

Shift a hex color lighter or darker.

Complementary Color

Opposite color on the wheel from any hex.

Color Mixer Calculator

Blend two hex colors by any ratio.

Grayscale Color Converter

Convert any hex color to grayscale.

Invert Color Calculator

Get the inverted negative of any hex color.

Readable Text Color

Black or white text for any background.

Tints & Shades Generator

Lighter tints and darker shades from a hex.

Analogous Colors

Neighbouring hues for a harmonious palette.

Three evenly spaced hues from one hex.

Random Hex Color

Generate random hex color codes.

PX to REM Converter

Convert pixels to rem for any root size.

REM to PX Converter

Convert rem to pixels for any root size.

Letter Spacing Converter

Letter-spacing px to em and tracking.

Line Height Calculator

Line-height in px and unitless from a ratio.

Golden Ratio Calculator

Golden-ratio sizes from any length.

Modular Scale Calculator

Type scale from a base size and ratio.

Breakpoint EM Converter

Pixel breakpoints to em media queries.

Aspect Ratio Padding

Padding-top % for responsive embeds.

Reading Time Calculator

Estimate reading time from word count.

CSS Triangle Generator

Pure-CSS triangles with the border trick.

Text Shadow Generator

Build CSS text-shadow declarations.

CSS Variables Generator

Name/value pairs into :root custom properties.

Srcset Generator

Build responsive image srcset attributes.

MIME Type Lookup

MIME content type for a file extension.

Common Port Lookup

Service for a well-known port number.

Compare two semantic version numbers.

User Agent Parser

Detect browser and OS from a UA string.

CSS Specificity Calculator

Selector specificity as an a,b,c triple.

ASCII Code Converter

Text to character codes and back.

Video File Size Calculator

Bitrate and duration to file size.

Audio File Size Calculator

Bitrate and length to MP3 size.

Image File Size Calculator

Width, height and bit depth to size.

Video Bitrate Calculator

Target size and length to bitrate.

Audio Bitrate Calculator

Target size and length to bitrate.

Streaming Data Usage Calculator

Bitrate and hours to GB used.

GIF Size Estimator

Dimensions and frames to GIF size.

RAW Photo Size Calculator

Megapixels and bit depth to RAW size.

Uncompressed Video Size Calculator

Resolution, fps and length to size.

Color Depth Size Calculator

Bit depth to image size and colors.

Frame Count Calculator

Duration and fps to total frames.

Timecode to Frames Converter

HH:MM:SS:FF timecode to frame number.

Frames to Timecode Converter

Frame number to HH:MM:SS:FF timecode.

Base64 Size Overhead Calculator

Byte length to encoded size and overhead.

Gzip Ratio Estimator

Original size and ratio to compressed size.

Cloud Storage Cost Calculator

GB stored and price to storage cost.

Bandwidth Cost Calculator

GB transferred and price to cost.

CDN Cost Calculator

Traffic and requests to CDN cost.

Egress Cost Calculator

Data out minus free tier to cost.

Backup Storage Size Calculator

Full and incremental backups to storage.

RAID Usable Capacity Calculator

Disk size, count and level to usable space.

Disk Fill Time Calculator

Free space and growth to time until full.

Transfer Time vs Size Calculator

File size and speed to transfer time.

API Payload Size Calculator

Records and bytes each to payload size.

Log Storage Growth Calculator

Log rate and retention to storage.

Database Table Size Calculator

Rows and row size to table size.

Photo Storage Count Calculator

Storage and photo size to photo count.

Music Storage Count Calculator

Storage and song size to song count.

4K Video Storage Calculator

Storage and bitrate to recording hours.

Camera Card Capacity Calculator

Card size to photos and video time.

Screen Recording Size Calculator

Bitrate and length to recording size.

Podcast Storage Calculator

Episodes and length to total storage.

DPI Print Size Calculator

Pixels and DPI to print dimensions.

Megapixel to Resolution Calculator

Megapixels and ratio to pixel size.

Aspect Ratio Resize Calculator

Original size and new width to new height.

Bitrate for Quality Calculator

Resolution and fps to recommended bitrate.

Ohm’s Law Calculator

V=IR and P=VI from any two values.

Voltage Divider Calculator

Vout = Vin×R2/(R1+R2).

Resistor Color Code

Decode band colors to ohms and tolerance.

LED Resistor Calculator

Series resistor = (Vs−Vf)/I.

Series Resistance

Total = R1 + R2 + R3 + R4.

Parallel Resistance

1/Rt = 1/R1 + 1/R2 + …

Capacitor Energy

E = ½CV², Q = CV.

RC Time Constant

τ = R×C, full charge ≈ 5τ.

RL Time Constant

τ = L/R, steady state ≈ 5τ.

LC Resonant Frequency

f = 1/(2π√(LC)).

Inductor Energy

Electrical Power

P = V×I×pf, S = V×I.

P = 10^((dBm−30)/10) watts.

Voltage Drop Calculator

Copper cable drop from length & area.

Wire Gauge Ampacity

AWG to diameter, area and amps.

Transformer Turns Ratio

n = Vp/Vs = Np/Ns = Is/Ip.

Vrms = Vpeak/√2 for a sine wave.

Three Phase Power

P = √3×VL×IL×pf.

Battery Life Calculator

Runtime = capacity/load × efficiency.

Battery Capacity

Wh = Ah × voltage.

Solar Panel Sizing

Array watts from daily Wh & sun hours.

Capacitor Charge Time

t = −RC×ln(1−Vc/Vs).

Coil Inductance

Single-layer air-core, Wheeler’s formula.

Quarter & half-wave from frequency.

dB = 10log(Po/Pi) or 20log(Vo/Vi).

Z = √(R²+(XL−XC)²).

Capacitive Reactance

Xc = 1/(2πfC).

Inductive Reactance

pf = real power / apparent power.

Energy Consumption Cost

kWh × rate over any period.

I = P / (V × pf).

P = V × I × pf.

kW = kVA × power factor.

Two Resistor Parallel

R = R1×R2/(R1+R2).

P = I²R, Q = I²Rt.

Slew Rate Calculator

SR = 2π × f × Vpeak.

Keyword Density Analyzer

Top words and density for SEO.

Meta Description Length Checker

Character length vs SEO limits.

Title Tag Length Checker

Title length vs 50-60 char limit.

Subnet Mask Calculator

CIDR prefix to mask, hosts and addresses.

CIDR to Netmask

Prefix length to dotted-decimal subnet mask.

Netmask to CIDR

Dotted-decimal mask to CIDR prefix length.

IPv4 address to binary and hex octets.

IP Class Finder

Classify any IPv4 as A/B/C/D/E, private or public.

Hosts Per Subnet

Usable hosts and addresses from a CIDR prefix.

Subnets and hosts when borrowing network bits.

Inverse mask for Cisco ACLs from a prefix.

Expand :: shorthand to full 8-group IPv6.

Colon, hyphen, Cisco and bare MAC formats.

File size and speed to download duration.

Data Usage Cost

Plan cost plus overage for extra gigabytes.

How much round-trip time is left for the network.

TCP maximum segment size from your MTU.

Network Throughput

Max TCP throughput from window and RTT.

File Transfer Time

Batch transfer duration with efficiency loss.

Streaming Bandwidth

Bandwidth and data for concurrent streams.

Usable space for RAID 0/1/5/6/10 arrays.

Does the backup fit the maintenance window?

Uptime Percentage

Uptime % from period and downtime minutes.

Allowed downtime for any SLA availability %.

Combine dependent service SLAs in series.

Packet Loss Impact

Loss percentage and quality from packet counts.

HTTP Request Size

Total bytes across a batch of HTTP requests.

Refresh rate and origin queries from a TTL.

Users Bandwidth

Total link size for concurrent users.

Concurrent call bandwidth by codec.

Latency vs Distance

Minimum latency from distance and medium.

TCP Window Size

Bandwidth-delay product for full link use.

IOPS and block size to throughput.

Will your traffic exceed the API quota?

Requests Per Second

Average and peak RPS from traffic totals.

Connection Pool

Pool size from RPS and latency.

Backend pool capacity with N+1 failover.

Compress CSS by removing comments and spaces.

Shrink HTML by stripping comments and whitespace.

Compact JSON by stripping whitespace.

JS Comment Remover

Delete // and /* */ comments from JS.

Whitespace Collapser

Collapse extra spaces, tabs and blank lines.

Extract plain text from HTML markup.

HTML Entities Encoder

Encode text into safe HTML entities.

Heading Outline Extractor

List H1–H6 headings as an indented outline.

Slug From Title

Make clean URL slugs from titles.

Words, reading time and SEO length check.

Image Alt Checker

Flag images with missing or empty alt.

Nofollow Link Builder

Generate rel="nofollow" anchor tags from URLs.

Sitemap Generator

Build sitemap.xml from a list of URLs.

Twitter Card Generator

Create Twitter/X card meta tags.

Canonical Tag Generator

Build a rel="canonical" link tag.

Hreflang Generator

Create hreflang alternate link tags.

Breadcrumb Schema

BreadcrumbList JSON-LD structured data.

Viewport Meta Generator

Create a mobile viewport meta tag.

Cache-Control Builder

Build a Cache-Control HTTP header.

Redirect Generator

Build 301/302 Apache and Nginx redirects.

UTM Link Builder

Build UTM-tagged campaign URLs.

Query String Builder

Build encoded URL query strings.

Breadcrumb Builder

Build accessible breadcrumb nav HTML.

SERP Snippet Preview

Preview title and description truncation.

Title Length Checker

Character and pixel length for title tags.

Meta Description Checker

Check meta description length for SEO.

URL Length Checker

Check URL length and path depth.

Recommended favicon sizes and link tags.

Above Fold Estimator

Is an element above the fold?

CSS Specificity Scorer

Score selector specificity (a,b,c).

Contrast Checker

WCAG contrast ratio for two colors.

Tap Target Checker

Check touch target size vs WCAG minimums.

Font Loading Strategy

font-display rules and preload snippets.

Critical CSS Size

Check critical CSS against the 14KB budget.

Page Weight Budget

Total page weight vs a performance budget.

More text & writing

Remove Empty Lines

Delete blank lines from any text.

Flip line order top to bottom.

Randomize the order of your lines.

Remove Extra Spaces

Collapse repeated spaces into one.

Add Line Numbers

Prefix each line with a number.

Character Count

Count characters with and without spaces.

Sentence Counter

Count sentences by end punctuation.

Paragraph Counter

Count paragraphs split by blank lines.

List each distinct word once.

Pull email addresses out of text.

Pull http and https links from text.

Extract Phone Numbers

Pull phone numbers out of text.

Extract Numbers

Pull integers and decimals from text.

Extract Hashtags

Pull hashtags out of any text.

Strip HTML Tags

Remove HTML markup, keep the text.

Remove Punctuation

Strip punctuation, keep words and spaces.

Strip diacritics into plain ASCII.

Delete every digit from your text.

Swap upper and lower case letters.

Convert space runs into tab characters.

Convert tabs into spaces, any width.

Trim whitespace from every line.

Add indentation to every line.

Word-wrap text to a fixed width.

Shorten text and add an ellipsis.

Camel Case Splitter

Split camelCase into readable words.

Snake to Title Case

Convert snake_case into Title Case.

Make tiny Unicode subscript characters.

Flip text into mirror writing.

Reverse Each Word

Flip letters within each word.

Text Statistics

Characters, words, lines, sentences, averages.

Syllable Counter

Estimate syllables in any text.

Alphabetize the words in your text.

Character Frequency

Count occurrences of each character.

Randomly mix upper and lower case.

Leetspeak Generator

Convert text into 1337 leetspeak.

APA Citation Generator

Author, year, title, source into APA format.

MLA Citation Generator

Author, title, container, publisher, year to MLA.

Chicago Citation Generator

Author, title, city, publisher, year to Chicago.

Reference List Formatter

Alphabetize and clean a reference list.

Name Numerology

Numerology number for any name.

Lucky Number Generator

A lucky number from your name or date.

Passphrase Generator

Memorable multi-word passphrases with a number.

Random 4, 6, or 8-digit numeric PINs.

Random Integer Generator

Random whole numbers in a min-max range.

Random Letter Generator

Random A-Z letters, single or in blocks.

Random Token Generator

Alphanumeric tokens of any length.

Polyhedral Dice Roller

Roll d4-d100 dice and sum the results.

Coin Toss Simulator

Batch coin tosses with heads/tails split.

Yes or No Decision

Random yes/no answer to any question.

Classic random fortune-telling answers.

Random Line Picker

Pick a random item from a list.

Split names into random balanced teams.

Secret Santa Generator

Random gift pairings, no self-draws.

Raffle Winner Picker

Draw a random winner from entries.

Random Word Generator

Random English words for games and prompts.

Random Username Generator

Adjective + noun + number usernames.

Random Color Generator

Random named color plus its hex code.

Random Emoji Generator

Random emoji, single or in a row.

Lorem List Generator

Placeholder bullet list items for mockups.

Placeholder Text Generator

Neutral filler paragraphs for mockups.

Random Date Generator

Random calendar dates for test data.

Random Time Generator

Random time of day, 24h or 12h.

Random Boolean Generator

Random true/false, 1/0, or on/off.

Gift Exchange Generator

Random mutual gift-exchange pairs.

Bingo Number Generator

Classic B-I-N-G-O 1-75 draws.

Lottery Number Generator

Random 6/49-style numbers plus a bonus.

Random Quote Generator

Random short motivational sayings.

Random Name Generator

Realistic first + last names for test data.

Dummy JSON Generator

Mock JSON user records for testing.

Random Hex String Generator

Random hex strings for tokens and IDs.

Random IPv4 Generator

Random IPv4 addresses for mock data.

Random MAC Address Generator

Random MAC addresses, colon or dash.

Random Phone Number Generator

Mock US phone numbers for test data.

Shuffle lines into random order.

Random Sample Picker

Sample N unique items from a list.

Weighted Random Picker

Random pick weighted by name:weight lines.

Pick one option at random from your list.

Flesch Reading Ease

Score text readability from 0 to 100.

Flesch-Kincaid Grade

US grade level of your writing.

Gunning Fog Index

Complexity from sentence and word length.

Grade level from polysyllabic words.

Coleman-Liau Index

Character-based readability grade.

Automated Readability Index

ARI grade from characters and words.

Reading Level Estimate

Flesch, Kincaid and Fog from counts.

Sentence Length Analyzer

Average, longest and shortest sentences.

Average Word Length

Mean letters per word in your text.

Passive Voice Detector

Flag passive voice in your writing.

Find and count -ly adverbs.

Filler Word Counter

Count just, really, very, actually…

Cliche Detector

Find tired, overused phrases.

Headline Analyzer

Score headlines for length and impact.

Keyword Extractor

Top recurring terms, minus stop words.

Longest Word Finder

List the longest words by length.

Word Diversity Ratio

Unique words over total words.

Speaking Time Estimate

How long your script takes to say.

Reading Time Estimate

Silent reading time for your text.

Subtitle Timing

On-screen duration for a caption.

Caption Length Checker

Fit captions to platform limits.

Tweet Length Counter

Weighted characters against 280.

SMS Segment Counter

GSM-7 vs UCS-2 segments and cost.

Count total and unique emoji.

Unicode Length Counter

Code points vs UTF-16 units.

Byte Length Counter

UTF-8 byte size of text.

Point value of words in Scrabble.

Group words that share endings.

Group words with the same letters.

Palindrome Detector

Find palindrome words in text.

Letter Frequency

Count each A–Z letter with bars.

Vowel & Consonant Counter

Count vowels vs consonants.

Capital Letter Counter

Uppercase, lowercase and CAPS words.

Whitespace Analyzer

Spaces, tabs, breaks and trailing space.

Duplicate Word Finder

List repeated words and their counts.

Text Similarity

Compare two texts for similarity.

More health & fitness

Carb Intake Calculator

Daily carbohydrate grams from your calories.

Fat Intake Calculator

Daily fat grams from your calories.

Fiber Intake Calculator

Recommended daily fiber from calories.

Calorie Deficit Calculator

Daily deficit for a weekly loss goal.

Calories To Lose Weight

Deficit to lose weight in a timeframe.

Maintenance Calories

Calories to hold your current weight.

Adjusted Body Weight

Ideal and adjusted weight from height.

Fat-Free Mass Index

FFMI and normalized FFMI from body fat.

Body Adiposity Index

BAI body-fat estimate from hip and height.

Ponderal Index Calculator

Height-cubed corrected body mass index.

Body Frame Size

Small, medium, or large frame from wrist.

Healthy Weight Range

Normal-BMI weight range for your height.

Weight Goal Date

Date you reach your goal weight.

Healthy body-fat percentage ranges by sex.

Resting Metabolic Rate

RMR from lean mass (Katch-McArdle).

Sodium Intake Calculator

Sodium vs limits and salt equivalent.

Sugar Intake Calculator

Added-sugar limits from your calories.

Caffeine Intake Calculator

Safe caffeine limit and coffee cups.

Alcohol Units Calculator

UK units from volume and ABV.

Standard Drinks Calculator

US standard drinks from volume and ABV.

Net Carbs Calculator

Total carbs minus fiber and sugar alcohols.

Glycemic Load Calculator

GL from glycemic index and carbs.

Calories In Vs Out

Energy balance and weekly weight trend.

Meal Calorie Split

Split daily calories across meals.

Kcal To kJ Converter

Convert kilocalories and kilojoules.

Iron Intake Calculator

Daily iron RDA by sex and age.

Weight Loss Percentage

Percent of body weight lost.

Protein Per Meal

Protein grams per meal from a daily goal.

Creatine Dosage Calculator

Loading and maintenance creatine doses.

Electrolyte Intake

Daily electrolyte targets by sex.

Daily Value Percentage

%DV from amount and reference value.

Keto Macros Calculator

Keto fat, protein, and carb grams.

Calories From Macros

Total calories from macro grams.

Sweat Rate Calculator

Hourly fluid loss during exercise.

Body Fat To Lose

Fat to lose for a goal body-fat percent.

Caffeine Half-Life

Caffeine remaining after a time period.

Rep Max Percentages

1RM percentage training loads and reps.

Powerlifting Wilks coefficient and score.

Modern DOTS powerlifting coefficient.

Target Heart Rate

Karvonen heart-rate training zone.

Fox, Tanaka, Nes and Gulati estimates.

VO2 Max Estimate

Estimate VO₂ max from resting heart rate.

Convert pace to km/h and mph.

Race Time Predictor

Predict race time with Riegel’s formula.

Finish time from pace and distance.

Even splits from a goal finish time.

Treadmill speed and incline to pace.

Swim pace per 100 m and 50 m.

Goal marathon time to required pace.

Half Marathon Pace

Goal half-marathon time to pace.

Goal 5K time to required pace.

VO₂ max from a 12-minute run.

Power-to-Weight

Cycling watts per kilogram.

FTP Power Zones

Coggan cycling power zones from FTP.

Calories Burned Running

Running calories via the MET method.

Calories Burned Cycling

Cycling calories via the MET method.

Calories Burned Walking

Walking calories via the MET method.

Steps to Calories

Step count to calories and distance.

Convert steps to miles and km.

Time to walk a distance at any speed.

Running Cadence

Cadence and stride to speed and pace.

Step and stride length from distance.

Running Economy

Oxygen cost of running per km.

Exercise Hydration

Fluid to drink during a workout.

Plank Progression

Weekly plank hold-time plan.

Accumulated sleep debt over days.

Wake time for power and cycle naps.

Jet Lag Adjustment

Days to adjust after crossing zones.

Gestational Age

Pregnancy weeks and days from LMP.

Conception Date

Estimate conception date from LMP.

Due Date from Ultrasound

Due date from scan gestational age.

Plates per side for any barbell target.

Bench Press Standards

Rate your bench vs strength standards.

Squat Standards

Rate your squat vs strength standards.

Deadlift Standards

Rate your deadlift vs strength standards.

Powerlifting Total

Squat + bench + deadlift total & split.

Sets × reps × weight training load.

Percentage-based training max from 1RM.

RPE to Percentage

Reps + RPE → %1RM and estimated max.

Rest Between Sets

Rest ranges by training goal.

Bulking Calories

Maintenance + surplus for lean bulking.

Cutting Calories

Maintenance − deficit for fat loss.

Body Recomposition

Maintenance calories + high protein for recomp.

Ramp calories back up week by week.

Training vs rest day macro targets.

Weekly Training Volume

Weekly sets & volume load per muscle.

Progressive Overload

Project weight gains over weeks.

Grip Strength Ratio

Grip strength per kg of bodyweight.

Vertical Jump Power

Peak power from jump height (Sayers).

Standing Broad Jump

Jump distance relative to height.

Distance & time → m/s, km/h, mph.

Mechanical work in joules from lifting.

Muscle Gain Rate

Realistic monthly muscle-gain potential.

Calorie Cycling

Weekly average from high & low days.

High-carb refeed calories & carb target.

Daily protein from g/kg bodyweight.

High / medium / low carb-day grams.

Reduced load & sets for a deload.

Strength-to-Weight

Lift as a multiple of bodyweight.

Relative Strength

Compare two lifters per unit bodyweight.

Allometric Scaling

Fair strength score across bodyweights.

Volume Landmarks

MV/MEV/MAV/MRV weekly sets per muscle.

Time Under Tension

Reps × tempo → seconds under load.

Workout Density

Volume load per minute of training.

Calories Per Workout

MET-based calories burned lifting.

Body Water Weight

Total body water & daily fluctuation.

Sodium for Pump

General daily & pre-workout sodium range.

Mean Arterial Pressure

MAP from systolic and diastolic BP.

Systolic minus diastolic pressure.

Perfusion pressure from a BP reading.

Corrected Calcium

Albumin-adjusted serum calcium.

Na − (Cl + HCO3) from electrolytes.

Kidney filtration from creatinine.

Creatinine Clearance

Cockcroft-Gault clearance estimate.

Heart-rate corrected QT interval.

LDL Cholesterol

Friedewald LDL from a lipid panel.

Cholesterol Ratio

Total-to-HDL cholesterol ratio.

A1C to Avg Glucose

HbA1c to estimated average glucose.

Average glucose to estimated HbA1c.

Nadler total blood volume estimate.

Drops per minute for an IV infusion.

Dosage by Weight

Weight-based mg dose and volume.

Weight-based daily and per-dose amounts.

Dose from body surface area.

Oxygen Tank Duration

Minutes of oxygen left at a flow rate.

Newborn 0-10 condition score.

Glasgow Coma Scale

Consciousness score from 3 to 15.

Burn TBSA (Rule of Nines)

Adult burn surface area estimate.

Parkland Formula

Burn fluid resuscitation over 24h.

Maintenance Fluids

Holliday-Segar 4-2-1 fluid needs.

Sodium needed to reach target level.

Serum Osmolality

Calculated osmolality from labs.

Bicarbonate Deficit

HCO3 needed to reach target.

Heart rate over systolic pressure.

Ideal Body Weight (Devine)

Devine ideal weight from height.

Adjusted Body Weight

Dosing weight from IBW and actual.

Fractional excretion of sodium.

Free Water Deficit

Water needed to correct hypernatremia.

Corrected Sodium (glucose)

Sodium adjusted for hyperglycemia.

Reticulocyte Index

Corrected retic and production index.

Absolute Neutrophil Count

ANC from WBC and neutrophil %.

Transferrin Saturation

Serum iron over TIBC, as a percent.

MCV divided by red cell count.

Pregnancy Week Calculator

Weeks pregnant from your last period.

Second Trimester Dates

Trimester start and end dates.

How many diapers to stock up.

Formula Amount Per Day

Daily formula from baby’s weight.

Baby Weight Percentile

Weight-for-age percentile, 0–24 months.

Baby Length Percentile

Length-for-age percentile, 0–24 months.

Head Circumference Percentile

Head circumference percentile by age.

Child Weight Percentile

Weight-for-age percentile, ages 2–6.

Child Height Predictor

Adult height from parents’ heights.

Feeding Schedule

Even feeding times across the day.

Baby Sleep Needs

Recommended sleep and naps by age.

Nap Transition Age

Typical nap count and next transition.

Breast Milk Storage

Safe storage times for expressed milk.

Weaning Schedule

How long gradual weaning takes.

Bottles Per Day

Bottles needed from daily ounces.

Baby Food Portions

Solid-food meals and portions by age.

Kids Water Intake

Daily fluid needs for children.

Kids Calorie Needs

Daily calories by age and activity.

Milestone Age Tracker

Baby age in months, weeks and days.

Typical baby tooth eruption order.

Immunization Schedule

Estimated childhood vaccine visit dates.

Screen Time Guideline

Recommended screen limits by age.

Potty Training Readiness

Readiness from age and signs.

Recommended car seat stage by size.

Pitcher earned run average from ER and IP.

Batting Average

Hits divided by at-bats (.XXX).

Slugging Percentage

Total bases per at-bat (SLG).

On-base plus slugging percentage.

WHIP Calculator

Walks + hits per inning pitched.

Basketball Game Score

Hollinger single-game efficiency rating.

True Shooting %

Scoring efficiency including free throws.

NFL Passer Rating

Official QB rating, 0 to 158.3.

NCAA Passer Rating

College passer efficiency rating.

Differential and index from a round.

Bowling Handicap

League average and handicap score.

Minimum darts to finish a score.

Points Per Game

Scoring average per game played.

Winning percentage from W-L-T record.

Games needed to clinch a division.

Pythagorean Wins

Expected win % from points scored/allowed.

New Elo after a match result.

Age-Grade Running

Age-graded race performance percentage.

Triathlon Total Time

Sum swim, bike, run and transitions.

Swim pace per 100 metres and speed.

Rowing Stroke Rate

Strokes per minute and 500m split.

Watts Per Kilogram

Cycling power-to-weight ratio (W/kg).

Vertical Jump Reach

Max touch height and hang time.

Football fantasy scoring (PPR toggle).

Goal Difference

Goal difference and league points.

Cricket Run Rate

Current and required run rate.

Tennis Game Odds

Game win probability from point odds.

Save Percentage

Goalie save % from shots and goals.

Expected Goals (xG)

Total xG vs actual goals scored.

More date & time

Days Between Dates

Days, weeks and months between two dates.

Hours Between Times

Duration between two clock times.

Add Days to a Date

Add days to a date for the result.

Subtract days from a date for the result.

Add Hours to a Time

Add hours to a clock time.

Ordinal day number within the year.

Quarter of Year

Which quarter a date falls in.

Find the next leap year.

Workdays Between

Mon-Fri working days between dates.

Weekend Counter

Saturdays and Sundays between dates.

Time Zone Offset

Difference between two UTC offsets.

Epoch timestamp to readable UTC date.

Calendar date to epoch timestamp.

Total days between birth and a date.

Decimal Hours to HMS

Decimal hours into H:M:S format.

Hours, minutes, seconds to decimal hours.

Countdown to a Date

Days remaining until a target date.

Human-friendly elapsed-time phrase.

Timesheet Hours Calculator

Hours worked from clock-in, clock-out and breaks.

Billable Hours Cost Calculator

Invoice amount from billable hours and rate.

Recurring Meeting Cost Calculator

Annual cost of a recurring team meeting.

Hourly Project Quote Calculator

Quote from hours, rate, contingency and expenses.

Time Tracking Total Calculator

Sum a list of time sessions into a total.

PTO Accrual Calculator

PTO balance from accrual rate and hours used.

Vacation Days Earned Calculator

Prorated vacation days from months worked.

Overtime Hours & Pay Calculator

Regular and overtime pay from total hours.

Shift Differential Pay Calculator

Premium pay from a shift differential percentage.

Timezone Meeting Planner

Convert a meeting time between UTC offsets.

Fiscal Quarter Calculator

Fiscal quarter for a date and FY start month.

Fiscal Year Week Calculator

Week number within a fiscal year from a date.

Days in Month Calculator

Days in any month, with leap-year support.

Elapsed Time Calculator

Days, hours and minutes between two datetimes.

Time Percentage of Day Calculator

Duration as a percentage of a day.

Pomodoro Planner Calculator

Total time for a run of pomodoro cycles.

Sprint Day Count Calculator

Working days and capacity hours in a sprint.

Deadline Working Days Calculator

Add business days to a date for a deadline.

Turnaround Time Calculator

Turnaround between request and resolution vs SLA.

Break-Even Hours Calculator

Monthly hours needed to cover fixed costs.

Freelance Hours Needed Calculator

Hours to reach an income goal at your rate.

Work Hours Per Year Calculator

Annual work hours after holidays and vacation.

Salary Per Hour Worked Calculator

Real hourly rate from an annual salary.

Time to Goal Hours Calculator

Weeks to reach an hours goal at a weekly pace.

Focus Time Ratio Calculator

Focus ratio from deep-work vs total hours.

Context Switch Cost Calculator

Time and money lost to context switching.

Time Blocking Schedule Calculator

How many focus blocks fit in available hours.

Part-Time vs Full-Time Hours

FTE and percentage from part-time hours.

Night Shift Hours Calculator

Hours for an overnight shift across midnight.

On-Call Pay Calculator

Standby plus call-out pay for on-call work.

Double-Time Pay Calculator

Pay for hours at a double-time multiplier.

Holiday Pay Calculator

Premium pay for hours worked on a holiday.

Accrued Hours Value Calculator

Cash value of accrued or banked hours.

Minutes to Hours Decimal

Convert minutes into decimal hours.

Time Card Rounding Calculator

Round clock times to payroll intervals.

Weekly Hours Average Calculator

Average weekly hours from a list of weeks.

More home & DIY

Wallpaper Calculator

Rolls needed from perimeter and roll size.

Flooring Calculator

Boxes needed from area and coverage.

Laminate Calculator

Planks needed from area and plank size.

Carpet Calculator

Carpet length, area and cost estimate.

Mulch Calculator

Mulch volume and bags from bed size.

Topsoil Calculator

Topsoil volume and tonnes from area.

Gravel Calculator

Gravel volume, tonnes and bags.

Turf rolls needed from lawn area.

Grass Seed Calculator

Seed weight from lawn area and rate.

Fertilizer Calculator

Fertilizer and nitrogen from area.

Deck Board Calculator

Boards and linear metres for a deck.

Fence Calculator

Posts, panels and rails for a fence.

Brick Calculator

Bricks needed from wall area.

Drywall Calculator

Plasterboard sheets from wall area.

Roof Pitch Calculator

Angle and slope factor from rise/run.

Weighted GPA from grades and credits.

Final Grade Calculator

Score needed on your final exam.

Appliance Cost Calculator

Running cost from wattage and rate.

Scale ingredient amounts up or down.

Ingredient Substitution

Tested swaps with exact amounts.

Bakers Percentage

Flour-relative percentages to gram weights.

Meat Cooking Time

Roast time from weight and doneness.

Turkey Thawing Time

Fridge or cold-water thaw by weight.

Turkey Roasting Time

Roast time for stuffed or unstuffed.

Steak grill time per side.

Cook time from thickness and doneness.

Salt for a wet brine by volume.

Bread Hydration

Dough hydration from flour and water.

Flour, water, salt and yeast per balls.

Spirit, sour and sweet by ratio.

Temp, time and leaves per tea type.

Dry pasta by people and portion.

Pizza Size Value

Which pizza is the better deal.

Calories Per Serving

Recipe calories divided by servings.

Food Cost Percentage

Ingredient cost against menu price.

Portion Per Person

Total food for a guest count.

Servings from a round cake diameter.

How much replacer per egg.

Sugar Substitute

Swap white sugar for sweeteners.

Flour Substitute

Swap all-purpose for other flours.

Starter Feeding

Flour and water to feed a starter.

Salt Brine Percentage

Equilibrium brine salt weight.

How long to marinate each protein.

Smoking Meat Time

Smoke time and target temp by cut.

Deep Fry Temperature

Oil temp and time per food.

Candy Temp Altitude

Altitude-adjusted candy temperature.

Whipped Cream Ratio

Sugar and vanilla for whipped cream.

Buttercream Ratio

Sugar and milk for buttercream.

Cream for chocolate by use.

Flour and fat to thicken liquid.

Water and mirepoix from bones.

Damped scaling for seasonings.

Solar Panel Savings

Yearly bill savings from a solar array.

Solar Panel Count

Panels needed for a target system size.

Battery Backup Time

Backup runtime from battery capacity.

Generator Sizing

Generator size from running and surge watts.

Monthly kWh Cost

Electricity cost from monthly kWh used.

Natural Gas Bill

Gas bill from therms and price.

Water Bill Estimate

Water bill from gallons used.

Seasonal Heating Cost

Cost to heat a home all season.

AC Running Cost

Cost to run air conditioning.

Insulation R-Value Savings

Savings from a higher R-value.

Household Carbon Footprint

CO2 from power, gas and driving.

Flight CO2 Emissions

Carbon emissions of a flight.

Driving CO2 Emissions

Carbon emissions from driving.

Tree Carbon Offset

Trees needed to offset CO2.

Phantom Load Cost

Yearly cost of standby power draw.

LED vs Incandescent

Yearly savings from switching to LED.

Shower Water Cost

Yearly water and cost of showers.

Toilet Flush Water

Yearly water used by flushing.

Gallons in a rectangular pool.

Pool Chlorine Dose

Chlorine needed to hit target ppm.

Pool Heating Cost

Cost to raise pool temperature.

Monthly cost to run a hot tub.

Propane Tank Duration

How long a propane tank lasts.

Wood Pellet Usage

Pellet bags and cost per season.

Thermostat Savings

Heating savings from a setback.

EV Charging Cost

Home charging cost for an EV.

Heat Pump Savings

Savings vs electric resistance heat.

Water Heater Cost

Yearly cost of heating water.

Dryer Cost Per Load

Cost to run a clothes dryer.

Dishwasher vs Hand

Water use: dishwasher vs hand.

Phantom Power Audit

Energy, cost and CO2 of standby draw.

Appliance Electricity Usage

Monthly kWh and cost of an appliance.

Gas vs Electric Heat

Yearly cost: gas vs electric heat.

Carbon emissions from electricity use.

Solar Payback Period

Years for solar to pay for itself.

Rainwater Tank Savings

Water harvested and cost saved.

Days Alive Calculator

How many days you have lived.

Weeks lived versus weeks remaining.

Heartbeats in a Lifetime

Total heartbeats from age and heart rate.

Breaths in a Lifetime

Total breaths from age and breathing rate.

Recommended sleep hours for your age.

Chinese Zodiac Finder

Your zodiac animal and element.

Birthstone by Month

Birthstone and flower for each month.

Generation Finder

Your generation from your birth year.

Adult Height Percentile

Where your height ranks among adults.

Coffee Cost per Year

Yearly cost of your coffee habit.

Smoking Cost per Year

Yearly cost of cigarettes.

Alcohol Cost per Year

Yearly spend on alcohol.

Bottled Water Cost

Yearly cost of bottled water.

Screen Time Cost

The value of your daily screen time.

Subscription Audit

Total up all your monthly subscriptions.

Phone Upgrade Cost

True yearly cost of a new phone.

Gift Budget Split

Spend per person from a gift budget.

Group Gift Split

Cost per person for a shared gift.

Wedding Budget Split

Allocate a wedding budget by category.

Gas Money Split

Split road-trip fuel cost per person.

Fair tip share by hours worked.

Drinks for a Party

How many drinks to buy for guests.

Pizzas for a Party

How many pizzas to order for guests.

Ice for a Party

How much ice to buy for guests.

Cups, napkins and plates to buy.

Seating Chart Tables

How many tables to seat your guests.

Potluck Planner

Dishes and drinks to cover a potluck.

Road Trip Snacks

Snacks and drinks to pack per trip.

Moving Boxes Estimator

Boxes needed to pack your home.

Chore Value Calculator

The value of your unpaid housework.

Commute Time per Year

Hours and days spent commuting yearly.

Movies Time Spent

Yearly hours spent watching movies.

Books Read per Year

Books you can finish in a year.

Steps to a Marathon

Steps and days to cover a marathon.

Plant Spacing Calculator

Plants per bed from spacing and dimensions.

Seed Quantity Calculator

Seeds needed adjusted for germination.

Row Crop Yield Calculator

Plants and yield from row layout.

Raised Bed Soil Calculator

Cubic feet, yards and bags for a bed.

Garden Soil Volume Calculator

Volume from area and spread depth.

Compost Ratio Calculator

Browns needed for balanced compost.

Lawn Area Calculator

Net turf area in sq ft, sq m, acres.

Garden Watering Calculator

Gallons to reach a target watering depth.

Greenhouse Heating Calculator

BTU/hr heat loss for a greenhouse.

Growing Degree Days Calculator

Daily GDD from temps and base.

Soil pH Adjustment Calculator

Lime to raise pH by soil type.

NPK Fertilizer Calculator

Product needed for a target N rate.

Chicken Feed Calculator

Flock feed in pounds and bags.

Livestock Water Calculator

Water needs by animal type and count.

Hay Bale Calculator

Bales needed from ration and days.

Crop Yield Estimate Calculator

Total yield and revenue from acreage.

Irrigation Flow Rate Calculator

GPM and GPH from a fill test.

Rainwater Harvest Calculator

Gallons harvested from roof and rain.

Sunlight Hours Calculator

Light hours for a target DLI.

Seed Starting Date Calculator

Indoor sowing date from last frost.

Transplant Date Calculator

Transplant date from sow date.

Pot Soil Volume Calculator

Potting mix for round containers.

Soil Drainage Rate Calculator

Perc rate from a drop-in-time test.

Pesticide Dilution Calculator

Concentrate and water for a spray mix.

Worm Bin Size Calculator

Bin area and worms from food scraps.

Pond Volume Calculator

Gallons and liters from pond size.

Drip Irrigation Calculator

Water applied per drip run.

Plant Population Calculator

Plants per acre from spacing.

Lime Application Calculator

Lime pounds and bags for an area.

Gypsum Application Calculator

Gypsum pounds and tons per acre.

Cover Crop Seed Calculator

Seed needed from rate and acres.

Tree Spacing Calculator

Trees per acre from spacing.

Greenhouse CO2 Calculator

CO2 to enrich a greenhouse.

Vapor pressure deficit from temp and RH.

Frost Protection Calculator

Frost risk and degrees of cover needed.

Garden ROI Calculator

ROI and net savings for a garden.

Photography & video

Near, far and total DoF for any lens.

Hyperfocal Distance

Max depth of field focus point.

Field of view from focal length and sensor.

Crop Equivalent Focal Length

Full-frame equivalent focal and aperture.

Exposure Value (EV)

EV from aperture and shutter speed.

Equivalent Exposure

New shutter speed for a new aperture.

Shutter speed for any aperture in sun.

ND Filter Exposure

Long-exposure time from ND stops.

Flash Guide Number

Aperture and range from a flash GN.

Print Size from Pixels

Print dimensions from pixels and DPI.

Max Print from Megapixels

Largest print size from your MP.

Megapixels from image dimensions.

Photo Aspect Ratio

Simplest ratio from width and height.

500 Rule Shutter

Max star shutter from focal length.

NPF Rule Shutter

Accurate max star shutter time.

Time-Lapse Clip Length

Clip length from interval and duration.

Time-Lapse Interval

Interval for a target clip length.

Diffraction Limit

Airy disk and diffraction-limited aperture.

Bellows Extension Factor

Extra exposure from magnification.

Video File Size

File size from bitrate and duration.

Required Video Bitrate

Bitrate from target size and duration.

Video Storage Per Hour

GB per hour from video bitrate.

Color Depth to Colors

Colors possible from a bit depth.

Aperture Stops Difference

Stops between two f-numbers.

Shutter Speed Stops

Stops between two shutter speeds.

ISO Stops Difference

Stops between two ISO values.

Field of View Width

Scene coverage at a subject distance.

Macro Magnification

Magnification from focal and distance.

Print Viewing Distance

Optimal distance for a print resolution.

Sensor Crop Factor

Crop factor from sensor dimensions.

Card Photo Capacity

Photos per card from average file size.

Screen Pixel Density

PPI from resolution and screen size.

Uncompressed Image Size

Raw file size from pixels and bit depth.

Duration from frames and frame rate.

Megapixels for Print

MP required for a print size and DPI.

Film Cost Per Shot

Total and per-frame film cost.

Focal Length for Framing

Lens needed to frame a subject width.

Flash Power Stops

Stops and guide number from power fraction.

Extension Tube Magnification

Added magnification from extension tubes.

Megapixel Print DPI

Achievable DPI from MP and print size.

Shutter Angle to Speed

Shutter speed from angle and frame rate.

Card Video Capacity

Recording time from card size and bitrate.

Focal Length Converter

Convert focal length between units.

Video Bitrate Converter

Convert bitrate between units.

Photo File Size Converter

Convert file sizes between units.

Music & audio

BPM to Delay Time

Note-synced delay times from your tempo.

BPM to Reverb Time

Reverb pre-delay and decay from tempo.

Note to Frequency

Note name and octave into Hz.

MIDI Note Frequency

MIDI number into frequency in Hz.

Frequency to Note

Nearest note and cents off from Hz.

Cents Between Notes

Interval in cents from two frequencies.

Semitones into a frequency ratio.

Transpose Frequency

Shift a pitch by semitones.

Octave Frequency

Shift a pitch by whole octaves.

PCM size from rate, depth and length.

Bitrate to File Size

Compressed size from bitrate and length.

Audio File Duration

Max minutes from file size and bitrate.

dB to Amplitude Ratio

Gain in dB into an amplitude ratio.

Amplitude Ratio to dB

Amplitude ratio into decibels.

Combine Decibel Levels

Add two sound levels in decibels.

Distance Attenuation

SPL drop over distance, inverse-square.

Sound Wavelength

Wavelength from frequency and speed.

Length of a bar from tempo and meter.

Samples Per Beat

Samples per beat from tempo and rate.

Vinyl Playing Time

Minutes per side from groove and RPM.

Tape Length to Time

Playing time from tape length and speed.

A4 Tuning Reference

Retune concert pitch from 440 Hz.

Harmonic Series

Overtone frequencies above a fundamental.

Headroom in dB below the ceiling.

LUFS Loudness Gain

Gain in dB to hit a LUFS target.

Beat Interval to BPM

Tempo from milliseconds between beats.

Convert dBu into dBV and voltage.

Audio Buffer Latency

Latency from buffer size and rate.

Speaker Delay Align

Delay in ms from speaker distance.

Streaming Data Usage

Mobile data from bitrate and hours.

Length of a note value from tempo.

Speed Pitch Shift

Pitch shift from a playback speed change.

Cents into a frequency ratio.

Frequency to MIDI Note

Frequency into a MIDI note number.

Samples to Time

Sample count into a duration.

Tempo into an LFO frequency in Hz.

Click Track Count

Clicks and bars from tempo and length.

Loop length from tempo, bars and rate.

Semitones to Cents

Semitones into cents and a ratio.

Italian tempo marking from a BPM.

Perceived Loudness

How a dB change sounds to the ear.

Crossover Frequency

First-order crossover from R and C.

Frequency Unit Converter

Convert Hz, kHz and MHz.

Audio Data Size Converter

Convert bytes, KB, MB and GB.

Bitrate Unit Converter

Convert bps, kbps and Mbps.

3D printing & making

Filament Length to Weight

Grams of filament from length and diameter.

Filament Weight to Length

Meters of filament from weight and diameter.

Filament Print Cost

Filament cost of a print from grams used.

Spool Remaining Length

Filament left on a spool by length.

Prints Per Spool

How many prints one spool yields.

Rough print time from volume and flow.

Number of layers from height and layer height.

Print Electricity Cost

Power cost of a print from watts and hours.

Total 3D Print Cost

Material, power, wear and labor combined.

Resin Print Cost

Resin cost of a model from mL used.

Volumetric Flow Rate

Flow from width, layer height and speed.

Max Print Speed

Top speed from flow, width and layer height.

Extrusion Width

Line width from nozzle diameter and factor.

New dimensions from a scale percentage.

Uniform Scale Factor

Scale percent to reach a target size.

Weight and cost from a model volume.

Shrinkage Compensation

Scale-up to offset material shrinkage.

First Layer Squish

First layer height vs nozzle diameter.

Bed Leveling Grid

Probe points and spacing for a mesh.

Spool Net Weight

Filament weight from gross minus empty.

Temperature Tower

Plan hotend temps for a calibration tower.

Heated Bed Power

Bed power and current from area.

Print Cooling Time

Cool-down time to a safe temperature.

Belt Steps Per mm

Steps/mm for a belt-driven axis.

Lead Screw Steps Per mm

Steps/mm for a lead-screw Z axis.

Timing Belt Length

Belt length from centres and pulley teeth.

Lead Screw Travel

Linear travel from lead and turns.

Infill Material Estimate

Plastic volume from solid volume and infill.

Filament Cross-Section

Cross-section area from filament diameter.

Convert mm, cm, inches, feet and thou.

Convert grams, kilograms, ounces and pounds.

Layer Height Micron

Convert microns, millimeters and thou.

Flow Calibration

New flow from measured wall thickness.

E-Steps Calibration

New E-steps from a measured extrusion.

Filament Price Per Meter

Price per meter from spool price and weight.

Print Farm Throughput

Prints per farm from uptime and time.

Resin Print Time

Resin layers and time from exposure settings.

Filament Usage Per Hour

Grams per hour from volumetric flow.

Minimum Layer Time

Slowdown to meet a minimum layer time.

Filament Remaining %

Percent of a spool left by weight.

3D Print Pricing

Sell price from cost plus a markup.

G-code Comment Remover

Strip comments and blank lines from G-code.

Convert cm3, mL, cubic inches and liters.

Convert mm/s, mm/min and inches per second.

Gaming & streaming

eDPI Calculator

Effective DPI from DPI and sensitivity.

cm/360 Calculator

Turn distance from DPI, sens and yaw.

Sensitivity Converter

Match sens between two games by yaw.

Sens from cm/360

In-game sens for a target cm/360.

Mouse Travel Distance

Physical distance from DPI and counts.

Polling Rate Interval

Report interval from mouse Hz.

Horizontal to Vertical FOV

vFOV from hFOV and aspect ratio.

Vertical to Horizontal FOV

hFOV from vFOV and aspect ratio.

Stretched Resolution

Stretch factor for a render resolution.

Black Bar Resolution

Image width and side bars, no stretch.

FPS to Frame Time

Frame time in ms from FPS.

Frame Time to FPS

FPS from a frame time in ms.

Refresh Rate Frame Time

Frame budget in ms from monitor Hz.

Response vs Frame Budget

Does response time fit one frame?

Total Input Lag

Peripheral, render and display latency.

Gacha Pull Probability

Chance of at least one hit in N pulls.

Pulls to First Drop

Average pulls for the first hit.

Drop Rate Kills

Average kills and odds for a rare drop.

Gacha Pity Planner

Pulls and cost to reach pity.

Currency to Pulls

Pulls you can afford from your balance.

XP to Next Level

XP remaining to your target level.

Battle Pass Tier

Days to finish from XP per day.

DPS from damage, speed and crits.

Health after armor reduction.

Crit Expected Damage

Average hit with crit factored in.

TTK from target HP and your DPS.

Farming rate from a session.

Grind Time to Goal

Hours to reach a currency goal.

Average value per box opened.

Kill/death ratio from your stats.

(Kills + assists) / deaths.

Win percentage from your record.

Headshot Percentage

Headshot rate from your kills.

Hit rate from shots fired.

Stream Data Per Hour

GB per hour from stream bitrate.

VOD Upload Time

Upload time from file size and speed.

Recording File Size

File size from bitrate and duration.

Upload Headroom

Spare upload above your stream bitrate.

Twitch Bits to USD

Revenue from cheered bits.

Sub Revenue Split

Take-home subs after the platform cut.

Earnings Per Hour

Stream income per hour streamed.

Donation Goal Progress

Progress and amount left to raise.

Viewer Bandwidth

Total outbound for all viewers.

Game Download Time

Download time from size and speed.

Streaming hours before a data cap.

Total latency from ping, tick and frame.

Tickrate Interval

Update interval from server tickrate.

Data Rate Converter

kbps, Mbps, MB/s and GB per hour.

Pets & animals

Dog Age in Human Years

Dog to human years by breed size.

Cat Age in Human Years

Convert cat years to human years.

Dog Daily Calories

Daily kcal from weight and activity.

Cat Daily Calories

Daily kcal from weight and status.

Dog Food Portions

Cups per day from calories and kcal/cup.

Cat Food Portions

Daily food from calories and kcal/cup.

Puppy Adult Weight

Estimate grown weight from current size.

Dog Water Intake

Daily water need from body weight.

Cat Water Intake

Daily water need from body weight.

Chocolate Toxicity

Theobromine risk by chocolate type.

Xylitol Toxicity

Xylitol risk by dose and dog weight.

Dog Benadryl Dosage

Diphenhydramine dose by dog weight.

Pet Medication Dose

Weight-based dose in mg and ml.

Dog Toxic Foods

Check if a food is safe for dogs.

Aquarium Volume

Gallons and liters of a rectangular tank.

Cylinder Tank Volume

Gallons and liters of a round tank.

Aquarium Volume Converter

Gallons, liters and cubic feet.

Fish Tank Stocking

Fish capacity by the inch-per-gallon rule.

Aquarium Heater Wattage

Heater size from liters and temp rise.

Aquarium Water Change

Volume to change from tank size and percent.

Aquarium Salt Dose

Freshwater salt by tank size and strength.

Marine Salt Mix

Salt mix for a target saltwater salinity.

Aquarium Surface Area

Water surface area for gas exchange.

Fish Tank Weight

Filled weight from volume and substrate.

Pet Insurance Break-Even

Premiums versus expected vet payout.

Daily, monthly and yearly food cost.

Food Bag Duration

How long a bag of food lasts.

Dog Treat Budget

Treat calories by the 10 percent rule.

Dog Walking Calories

Owner calories burned on a dog walk.

Weight from heart girth and body length.

Daily ration as a percent of body weight.

Rabbit Food Portions

Daily pellets and greens by weight.

Guinea Pig Vitamin C

Daily vitamin C needs by body weight.

Bird Food Amount

Daily food as a share of body weight.

Bird Cage Bar Spacing

Safe bar spacing by bird species.

Litter Box Count

Boxes by the one-per-cat-plus-one rule.

Cat Litter Usage

Monthly litter use by cats and type.

Kitten Age Stage

Development stage from age in weeks.

Pet Gestation Countdown

Days remaining by species and days bred.

Reptile Heat Wattage

Starting basking bulb wattage estimate.

Small Pet Cage Size

Minimum floor area by species and count.

Minimum crate length and height.

Pet Age in Months

Convert pet age to months and weeks.

Pavement Paw Safety

Paw safety from air temperature.

Puppy Vaccine Schedule

Typical vaccines due by age in weeks.

Aviation & weather

Density Altitude

From pressure altitude and temperature.

Pressure Altitude

From elevation and altimeter setting.

Crosswind Component

Crosswind and headwind for a runway.

TAS from IAS with the 2% rule.

Ground speed from TAS and wind.

Dew point from temp and humidity.

Relative Humidity

Humidity from temp and dew point.

Cloud base from temp / dew point spread.

Wind Chill Index

How cold it feels with the wind.

How hot it feels with humidity.

Feels Like Temperature

Apparent temp from heat, humidity, wind.

Wet Bulb Temperature

Wet-bulb from temp and humidity.

ISA Temperature

Standard temperature at any altitude.

OAT versus standard temperature.

Speed of sound at any altitude.

Mach from true airspeed and altitude.

Glideslope Descent Rate

Descent rate for a glideslope angle.

Where to start your descent.

Descent Gradient

Gradient from altitude loss and distance.

Gradient and rate from height and distance.

Flight time from fuel and burn rate.

Fuel for a distance plus reserve.

Nautical miles per gallon of fuel.

Great Circle Distance

Distance between two lat/lon points.

Initial Bearing

True course between two lat/lon points.

Beaufort force from wind speed.

Altimeter Error

Altitude error from a wrong setting.

Runway Length Correction

Adjust takeoff distance for conditions.

Wind Correction Angle

Crab angle and ground speed from wind.

Fuel gallons into pounds and kilograms.

Time en route from distance and speed.

Point of No Return

Time and distance you can still turn back.

Air density from pressure and temperature.

Absolute Humidity

Grams of water vapor per cubic meter.

Humidex from temperature and dew point.

Standard Rate Bank

Bank angle for a standard rate turn.

Turn radius from speed and bank angle.

Temperature Conversion

Celsius, Fahrenheit and Kelvin at once.

Temperature Lapse Rate

Temperature aloft from a lapse rate.

Wind Gust Factor

Gust factor and approach speed additive.

Saturation Vapor Pressure

Vapor pressure and deficit from humidity.

Airspeed Converter

Knots, mph, km/h and m/s.

Altitude in feet, meters and kilometers.

Nautical Miles Converter

Nautical miles, km and statute miles.

Altimeter Pressure

inHg, hPa, millibars and mmHg.

Visibility Converter

Statute miles, km, meters, nautical miles.