Week Number
Select a date to see which week number it is.
Week Number
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Year
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Day of Week
Related calculators
ISO Week Number for a Date
Choose any calendar date to see its ISO 8601 week number, which ISO week-year it belongs to, and the weekday name. Handy for Swedish planning where vecka matters more than the day-of-month alone.
How to use
Pick Date. Read week number, year, and weekday in the results.
Example
14 August 2026 shows which vecka it falls in for meeting invites that say "v.33" instead of a long date string.
Tips
ISO weeks start on Monday; week 1 is the week with the year first Thursday. This differs from US week systems some apps use.