2028 has 52 ISO weeks.
Week 1 runs January 3 to January 9, and week 52 ends December 31. Weeks run Monday to Sunday, following ISO 8601.
- Weeks
- 52
- Week 1 starts
- January 3
- Week 52 ends
- December 31
- Standard
- ISO 8601
| Week | Starts (Monday) | Ends (Sunday) |
|---|---|---|
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| 52 |
Why 2028 has 52 weeks
Under ISO 8601 a week belongs to the year that contains its Thursday. That gives every year either 52 or 53 whole weeks and never splits one across a year boundary. A year gets 53 when it starts on a Thursday, or on a Wednesday in a leap year.
ISO weeks versus US week numbering
The two conventions disagree. ISO weeks start on Monday, and week 1 is the week holding the first Thursday. The common North American convention starts weeks on Sunday and calls the week containing 1 January week 1, which can produce a short first week. Payroll, retail, and broadcast calendars often use the latter. If a week number here disagrees with one from another system, this is usually why.
Week numbers by month
Each month page shows the ISO weeks it spans:
- January2028
- February2028
- March2028
- April2028
- May2028
- June2028
- July2028
- August2028
- September2028
- October2028
- November2028
- December2028
Other years
- 2026 week numbers — 53 weeks
- 2027 week numbers — 52 weeks
- 2029 week numbers — 52 weeks
- 2030 week numbers — 52 weeks