Find the ISO-8601 week number for any date — with its day of year, quarter and weekday — or work backwards from a year and week to the exact Monday–Sunday range. All calculated live in your browser, nothing ever leaves your device.
Calculating the current week…
Uses ISO-8601 rules: weeks start on Monday, and week 1 is the week containing the first Thursday of the year.
Enter an ISO year and week number to reveal that week's Monday-to-Sunday date range.