What Week Number Is It?
Current ISO 8601 Week
--
About ISO Week Numbers
ISO 8601 defines the week number system used internationally. Key rules:
- Weeks start on Monday
- Week 1 is the week containing the first Thursday of the year
- A year has either 52 or 53 weeks
- December 29-31 may belong to week 1 of the next year, and January 1-3 may belong to the last week of the previous year
Try the full Week Number tool to look up any date.