How many weeks are in 2028?
2028 has 52 weeks in ISO 8601, because it starts on a Saturday and, although it is a leap year, that is not enough for a 53rd week. In the US system, where week 1 is the week of January 1 and partial weeks count, 2028 runs from week 1 to week 54: January 1 is a Saturday and December 31 a Sunday, so each sits alone in its own week. The last US week starts on Sunday, Dec 31, 2028.
January 1 to 2, 2028 still belong to ISO week 52 of 2027, so ISO week 1 starts on Monday, Jan 3, 2028. The last ISO week, week 52, ends on Sunday, Dec 31, 2028.
US week 1 runs from Dec 26, 2027 to Jan 1, 2028. Because US weeks start on Sunday and ISO weeks on Monday, the same number never covers exactly the same days. In 2028 the gap is a full week for most of the year: from Monday to Saturday, the US number is one higher than the ISO number (ISO week 10 is US week 11), and on Sundays it is two higher.
Weeks month by month
January: US weeks 1 to 6; February: US weeks 6 to 10; March: US weeks 10 to 14; April: US weeks 14 to 19; May: US weeks 19 to 23; June: US weeks 23 to 27; July: US weeks 27 to 32; August: US weeks 32 to 36; September: US weeks 36 to 40; October: US weeks 41 to 45; November: US weeks 45 to 49; December: US weeks 49 to 54. In ISO numbering, January 2028 starts in week 52 (of 2027) and December ends in week 52.
2028 week numbers with dates
| Week | US (Sunday to Saturday) | ISO 8601 (Monday to Sunday) |
|---|---|---|
| 1 | Dec 26, 2027 to Jan 1 | Jan 3 to Jan 9 |
| 2 | Jan 2 to Jan 8 | Jan 10 to Jan 16 |
| 3 | Jan 9 to Jan 15 | Jan 17 to Jan 23 |
| 4 | Jan 16 to Jan 22 | Jan 24 to Jan 30 |
| 5 | Jan 23 to Jan 29 | Jan 31 to Feb 6 |
| 6 | Jan 30 to Feb 5 | Feb 7 to Feb 13 |
| 7 | Feb 6 to Feb 12 | Feb 14 to Feb 20 |
| 8 | Feb 13 to Feb 19 | Feb 21 to Feb 27 |
| 9 | Feb 20 to Feb 26 | Feb 28 to Mar 5 |
| 10 | Feb 27 to Mar 4 | Mar 6 to Mar 12 |
| 11 | Mar 5 to Mar 11 | Mar 13 to Mar 19 |
| 12 | Mar 12 to Mar 18 | Mar 20 to Mar 26 |
| 13 | Mar 19 to Mar 25 | Mar 27 to Apr 2 |
| 14 | Mar 26 to Apr 1 | Apr 3 to Apr 9 |
| 15 | Apr 2 to Apr 8 | Apr 10 to Apr 16 |
| 16 | Apr 9 to Apr 15 | Apr 17 to Apr 23 |
| 17 | Apr 16 to Apr 22 | Apr 24 to Apr 30 |
| 18 | Apr 23 to Apr 29 | May 1 to May 7 |
| 19 | Apr 30 to May 6 | May 8 to May 14 |
| 20 | May 7 to May 13 | May 15 to May 21 |
| 21 | May 14 to May 20 | May 22 to May 28 |
| 22 | May 21 to May 27 | May 29 to Jun 4 |
| 23 | May 28 to Jun 3 | Jun 5 to Jun 11 |
| 24 | Jun 4 to Jun 10 | Jun 12 to Jun 18 |
| 25 | Jun 11 to Jun 17 | Jun 19 to Jun 25 |
| 26 | Jun 18 to Jun 24 | Jun 26 to Jul 2 |
| 27 | Jun 25 to Jul 1 | Jul 3 to Jul 9 |
| 28 | Jul 2 to Jul 8 | Jul 10 to Jul 16 |
| 29 | Jul 9 to Jul 15 | Jul 17 to Jul 23 |
| 30 | Jul 16 to Jul 22 | Jul 24 to Jul 30 |
| 31 | Jul 23 to Jul 29 | Jul 31 to Aug 6 |
| 32 | Jul 30 to Aug 5 | Aug 7 to Aug 13 |
| 33 | Aug 6 to Aug 12 | Aug 14 to Aug 20 |
| 34 | Aug 13 to Aug 19 | Aug 21 to Aug 27 |
| 35 | Aug 20 to Aug 26 | Aug 28 to Sep 3 |
| 36 | Aug 27 to Sep 2 | Sep 4 to Sep 10 |
| 37 | Sep 3 to Sep 9 | Sep 11 to Sep 17 |
| 38 | Sep 10 to Sep 16 | Sep 18 to Sep 24 |
| 39 | Sep 17 to Sep 23 | Sep 25 to Oct 1 |
| 40 | Sep 24 to Sep 30 | Oct 2 to Oct 8 |
| 41 | Oct 1 to Oct 7 | Oct 9 to Oct 15 |
| 42 | Oct 8 to Oct 14 | Oct 16 to Oct 22 |
| 43 | Oct 15 to Oct 21 | Oct 23 to Oct 29 |
| 44 | Oct 22 to Oct 28 | Oct 30 to Nov 5 |
| 45 | Oct 29 to Nov 4 | Nov 6 to Nov 12 |
| 46 | Nov 5 to Nov 11 | Nov 13 to Nov 19 |
| 47 | Nov 12 to Nov 18 | Nov 20 to Nov 26 |
| 48 | Nov 19 to Nov 25 | Nov 27 to Dec 3 |
| 49 | Nov 26 to Dec 2 | Dec 4 to Dec 10 |
| 50 | Dec 3 to Dec 9 | Dec 11 to Dec 17 |
| 51 | Dec 10 to Dec 16 | Dec 18 to Dec 24 |
| 52 | Dec 17 to Dec 23 | Dec 25 to Dec 31 |
| 53 | Dec 24 to Dec 30 | No ISO week 53 |
| 54 | Dec 31 to Jan 6, 2029 | No ISO week 54 |
Holidays by week number in 2028
Federal holidays and Easter, with their week in each system. 12 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: New Year’s Day (Saturday, observed Fri, Dec 31); Veterans Day (Saturday, observed Fri, Nov 10).
| Holiday | Date | US week | ISO week |
|---|---|---|---|
| New Year’s Day | Sat, Jan 1 (observed Fri, Dec 31) | 1 | 52 |
| Martin Luther King Jr. Day | Mon, Jan 17 | 4 | 3 |
| Presidents’ Day | Mon, Feb 21 | 9 | 8 |
| Easter Sunday | Sun, Apr 16 | 17 | 15 |
| Memorial Day | Mon, May 29 | 23 | 22 |
| Juneteenth | Mon, Jun 19 | 26 | 25 |
| Independence Day | Tue, Jul 4 | 28 | 27 |
| Labor Day | Mon, Sep 4 | 37 | 36 |
| Columbus Day | Mon, Oct 9 | 42 | 41 |
| Veterans Day | Sat, Nov 11 (observed Fri, Nov 10) | 46 | 45 |
| Thanksgiving | Thu, Nov 23 | 48 | 47 |
| Christmas Day | Mon, Dec 25 | 53 | 52 |
Writing a date as an ISO week date
ISO 8601 can also write a date as year, week and weekday. Thanksgiving 2028, Nov 23, 2028, becomes 2028-W47-4: week 47, day 4 (Thursday). Christmas Day becomes 2028-W52-1. Planning tools and some spreadsheets accept this form directly.
Other years: week numbers 2027 and week numbers 2029. 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.