Week number of the year
See which week of the year it is today or on any date, using the ISO 8601 standard, with the day of the year, the days left and a list of every week with its start and end dates.
How to useWhat week of the year is it?
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Week number of the year: what it is for
Choose a date and see the week number using the ISO 8601 standard, with weeks starting on Monday. The tool also shows the day of the year, how many days are left in the year and a table of every week of the year.
How to use
- Choose a date or use today's.
- See the week number.
- Check the table of weeks in the year.
When to use it
- Planning sprints and schedules.
- Filling in weekly reports.
- Checking an order's delivery week.
Frequently asked questions
How are weeks numbered?
Using the ISO 8601 standard, common in calendars and businesses: weeks start on Monday and week 1 is the one that contains the year's first Thursday. That's why some days in early January can belong to the last week of the previous year.
Does a year have 52 or 53 weeks?
Most have 52. Years that start on a Thursday, or leap years that start on a Wednesday, have 53 ISO weeks.
Is it really free?
Yes, 100% free. No sign-up, no subscription and no usage limits. All Tools123 tools are free and run right in your browser.