What Week Is It? Week Number
Current ISO week number and the week of any date. Free, no sign-up, works in your browser.
Today is week
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How to use the week number
- The current ISO week number is shown at the top.
- Pick any date to see which week it falls in, with that week’s Monday and Sunday.
- Change the year to see the full list of weeks — 52 or 53.
ISO 8601 weeks start on Monday, and week 1 is the week with the year’s first Thursday — the standard in Ireland, the UK and most of Europe, used for school planners, shift rotas, delivery schedules and payroll. Some years, like 2026, have 53 weeks.