How many weeks are in 2029?
2029 has 52 weeks in ISO 8601, because it starts on a Monday. In the US system, where week 1 is the week of January 1 and partial weeks count, 2029 runs from week 1 to week 53. The last US week starts on Sunday, Dec 30, 2029.
January 1 is a Monday, so ISO week 1 starts on January 1 itself and the two systems line up at the start of the year. At the other end, the days from Dec 31, 2029 on are already ISO week 1 of 2030.
US week 1 runs from Dec 31, 2028 to Jan 6, 2029. Because US weeks start on Sunday and ISO weeks on Monday, the same number never covers exactly the same days. For most of 2029, a date has the same number in both systems from Monday to Saturday, and the US number is one higher on Sundays.
Weeks month by month
January: US weeks 1 to 5; February: US weeks 5 to 9; March: US weeks 9 to 13; April: US weeks 14 to 18; May: US weeks 18 to 22; June: US weeks 22 to 26; July: US weeks 27 to 31; August: US weeks 31 to 35; September: US weeks 35 to 40; October: US weeks 40 to 44; November: US weeks 44 to 48; December: US weeks 48 to 53. In ISO numbering, January 2029 starts in week 1 and December ends in week 1 (of 2030).
2029 week numbers with dates
| Week | US (Sunday to Saturday) | ISO 8601 (Monday to Sunday) |
|---|---|---|
| 1 | Dec 31, 2028 to Jan 6 | Jan 1 to Jan 7 |
| 2 | Jan 7 to Jan 13 | Jan 8 to Jan 14 |
| 3 | Jan 14 to Jan 20 | Jan 15 to Jan 21 |
| 4 | Jan 21 to Jan 27 | Jan 22 to Jan 28 |
| 5 | Jan 28 to Feb 3 | Jan 29 to Feb 4 |
| 6 | Feb 4 to Feb 10 | Feb 5 to Feb 11 |
| 7 | Feb 11 to Feb 17 | Feb 12 to Feb 18 |
| 8 | Feb 18 to Feb 24 | Feb 19 to Feb 25 |
| 9 | Feb 25 to Mar 3 | Feb 26 to Mar 4 |
| 10 | Mar 4 to Mar 10 | Mar 5 to Mar 11 |
| 11 | Mar 11 to Mar 17 | Mar 12 to Mar 18 |
| 12 | Mar 18 to Mar 24 | Mar 19 to Mar 25 |
| 13 | Mar 25 to Mar 31 | Mar 26 to Apr 1 |
| 14 | Apr 1 to Apr 7 | Apr 2 to Apr 8 |
| 15 | Apr 8 to Apr 14 | Apr 9 to Apr 15 |
| 16 | Apr 15 to Apr 21 | Apr 16 to Apr 22 |
| 17 | Apr 22 to Apr 28 | Apr 23 to Apr 29 |
| 18 | Apr 29 to May 5 | Apr 30 to May 6 |
| 19 | May 6 to May 12 | May 7 to May 13 |
| 20 | May 13 to May 19 | May 14 to May 20 |
| 21 | May 20 to May 26 | May 21 to May 27 |
| 22 | May 27 to Jun 2 | May 28 to Jun 3 |
| 23 | Jun 3 to Jun 9 | Jun 4 to Jun 10 |
| 24 | Jun 10 to Jun 16 | Jun 11 to Jun 17 |
| 25 | Jun 17 to Jun 23 | Jun 18 to Jun 24 |
| 26 | Jun 24 to Jun 30 | Jun 25 to Jul 1 |
| 27 | Jul 1 to Jul 7 | Jul 2 to Jul 8 |
| 28 | Jul 8 to Jul 14 | Jul 9 to Jul 15 |
| 29 | Jul 15 to Jul 21 | Jul 16 to Jul 22 |
| 30 | Jul 22 to Jul 28 | Jul 23 to Jul 29 |
| 31 | Jul 29 to Aug 4 | Jul 30 to Aug 5 |
| 32 | Aug 5 to Aug 11 | Aug 6 to Aug 12 |
| 33 | Aug 12 to Aug 18 | Aug 13 to Aug 19 |
| 34 | Aug 19 to Aug 25 | Aug 20 to Aug 26 |
| 35 | Aug 26 to Sep 1 | Aug 27 to Sep 2 |
| 36 | Sep 2 to Sep 8 | Sep 3 to Sep 9 |
| 37 | Sep 9 to Sep 15 | Sep 10 to Sep 16 |
| 38 | Sep 16 to Sep 22 | Sep 17 to Sep 23 |
| 39 | Sep 23 to Sep 29 | Sep 24 to Sep 30 |
| 40 | Sep 30 to Oct 6 | Oct 1 to Oct 7 |
| 41 | Oct 7 to Oct 13 | Oct 8 to Oct 14 |
| 42 | Oct 14 to Oct 20 | Oct 15 to Oct 21 |
| 43 | Oct 21 to Oct 27 | Oct 22 to Oct 28 |
| 44 | Oct 28 to Nov 3 | Oct 29 to Nov 4 |
| 45 | Nov 4 to Nov 10 | Nov 5 to Nov 11 |
| 46 | Nov 11 to Nov 17 | Nov 12 to Nov 18 |
| 47 | Nov 18 to Nov 24 | Nov 19 to Nov 25 |
| 48 | Nov 25 to Dec 1 | Nov 26 to Dec 2 |
| 49 | Dec 2 to Dec 8 | Dec 3 to Dec 9 |
| 50 | Dec 9 to Dec 15 | Dec 10 to Dec 16 |
| 51 | Dec 16 to Dec 22 | Dec 17 to Dec 23 |
| 52 | Dec 23 to Dec 29 | Dec 24 to Dec 30 |
| 53 | Dec 30 to Jan 5, 2030 | No ISO week 53 |
Holidays by week number in 2029
Federal holidays and Easter, with their week in each system. 2 of these 12 dates have a different number in the two systems, so say which one you mean when you plan around them. Falling on a weekend this year: Veterans Day (Sunday, observed Mon, Nov 12).
| Holiday | Date | US week | ISO week |
|---|---|---|---|
| New Year’s Day | Mon, Jan 1 | 1 | 1 |
| Martin Luther King Jr. Day | Mon, Jan 15 | 3 | 3 |
| Presidents’ Day | Mon, Feb 19 | 8 | 8 |
| Easter Sunday | Sun, Apr 1 | 14 | 13 |
| Memorial Day | Mon, May 28 | 22 | 22 |
| Juneteenth | Tue, Jun 19 | 25 | 25 |
| Independence Day | Wed, Jul 4 | 27 | 27 |
| Labor Day | Mon, Sep 3 | 36 | 36 |
| Columbus Day | Mon, Oct 8 | 41 | 41 |
| Veterans Day | Sun, Nov 11 (observed Mon, Nov 12) | 46 | 45 |
| Thanksgiving | Thu, Nov 22 | 47 | 47 |
| Christmas Day | Tue, Dec 25 | 52 | 52 |
Writing a date as an ISO week date
ISO 8601 can also write a date as year, week and weekday. Thanksgiving 2029, Nov 22, 2029, becomes 2029-W47-4: week 47, day 4 (Thursday). Christmas Day becomes 2029-W52-2. Planning tools and some spreadsheets accept this form directly.
Other years: week numbers 2028 and week numbers 2030. For any single date, the week number tool gives the week in one tap, and the day of the week calculator tells you which weekday it falls on.