Current Week Number
27
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June 2026 Calendar with Week Numbers
| Week | Mon | Tue | Wed | Thu | Fri | Sat | Sun |
|---|---|---|---|---|---|---|---|
| 23 | 1 | 2 | 3 | 4 | 5 | 6 | 7 |
| 24 | 8 | 9 | 10 | 11 | 12 | 13 | 14 |
| 25 | 15 | 16 | 17 | 18 | 19 | 20 | 21 |
| 26 | 22 | 23 | 24 | 25 | 26 | 27 | 28 |
| 27 | 29 | 30 | 1 | 2 | 3 | 4 | 5 |
* The highlighted row represents the current ISO-8601 week.
Holidays This Week
FAQ — ISO Week Numbers
Common questions about this page — answers customized for the data shown above.
ISO 8601 week numbering assigns every week of the year a number from 1 to 52 (or 53). Weeks run Monday–Sunday. Week 1 is the week containing the first Thursday of the year (equivalently, the week containing January 4). Years can have either 52 or 53 ISO weeks depending on which day January 1 falls on.
The live counter above shows this week's ISO week number, updated automatically. It increments every Monday at midnight local time and rolls back to Week 1 each new ISO year.
Different conventions exist. The US 'week of the year' often counts weeks starting on Sunday and treats January 1 as Week 1 regardless of day. ISO (common in Europe and in most software) uses Monday-start weeks with the January-4 rule. Time.so always shows the ISO week.
Yes — early January days can belong to the last ISO week of the previous calendar year, and late December days can belong to ISO Week 1 of the following year. For example, December 31, 2025 (a Wednesday) belongs to ISO Week 1 of 2026.
Years where January 1 falls on a Thursday have 53 ISO weeks. Leap years where January 1 is a Wednesday also have 53. This happens roughly every 5–6 years.
The Time.so calendar shows ISO week numbers on each row of the month grid. For counting down to upcoming weeks (or any future date), use live countdowns.
ISO week numbers are widely used in scheduling, project management, payroll, manufacturing, and supply-chain planning — especially in Europe. Saying 'we'll deliver in Week 32' is unambiguous and language-independent, unlike date formats that vary by country.
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All Weeks in 2026
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Click any number above to view specific dates, holidays, and details for that week of the year.
How to show week numbers in...
Instructions and snippets for calendar apps, spreadsheets, and programming languages.
Standard: ISO 8601
The ISO 8601 standard is the international agreement for representing dates and times. It defines the week as starting on Monday and Week 1 as the week containing the first Thursday of the year.