Week 21 in 2109
Week 21 of 2109 begins on May 20, 2109 and ends on May 26, 2109. It covers days 140 to 146 of the year and falls in quarter 2.
Weeks until this week: 4313
Week 21 of 2109 at a glance
| Starts (Monday) | May 20, 2109 |
|---|---|
| Ends (Sunday) | May 26, 2109 |
| US week (Sunday to Saturday) | 21 (May 19, 2109) |
| Month | May |
| Quarter | Q2 |
| Days of the year | 140–146 |
| Year completed at the end of this week | 40.0% |
| Weeks left in 2109 after this week | 31 |
| Weeks in 2109 | 52 |
| Even or odd week | Odd |
Calendar for May 2109
Download Calendar in printable A4 PDF
(US version) (EU/ISO Version)
All Weeks in 2109:
Past & Future Week Number 21:
US and ISO week numbers
In the US system, where weeks start on Sunday and week 1 is the week that contains 1 January, this is week 21 of 2109. It runs from May 19, 2109 to May 25, 2109.
Even and odd weeks
Week 21 is an odd week. Even and odd week numbers are used for alternating schedules such as shift rotas, school timetables, custody arrangements and waste collection.
Week 21 in other years
| From | To | |
|---|---|---|
| Week 21 in 2107 | May 23, 2107 | May 29, 2107 |
| Week 21 in 2108 | May 21, 2108 | May 27, 2108 |
| Week 21 in 2110 | May 19, 2110 | May 25, 2110 |
| Week 21 in 2111 | May 18, 2111 | May 24, 2111 |
How week numbers are counted
Most of the world numbers weeks according to the ISO 8601 standard. A week starts on Monday, and week 1 is the week that contains the first Thursday of the year, which is always the week that contains 4 January.
Week 1 of 2109 began on December 31, 2108. 2109 has 52 ISO weeks.
Because of this rule, the first days of January can belong to the last week of the previous year, and the last days of December can belong to week 1 of the next year.
In the United States, weeks usually start on Sunday and week 1 is the week that contains 1 January, so the US week number can differ from the ISO week number.
Frequently Asked Questions (FAQ)
When does week 21 of 2109 start and end?
Week 21 of 2109 starts on May 20, 2109 and ends on May 26, 2109 (ISO 8601, Monday to Sunday).
Which month is week 21 of 2109 in?
Week 21 of 2109 is in May.
What dates are in week 21 of 2109?
May 20, 2109, May 21, 2109, May 22, 2109, May 23, 2109, May 24, 2109, May 25, 2109, and May 26, 2109
How many weeks does 2109 have?
2109 has 52 ISO weeks.
Is week 21 an even or odd week?
Week 21 is an odd week.
What is the US week number for this week?
In the US system, where weeks start on Sunday and week 1 is the week that contains 1 January, this is week 21 of 2109. It runs from May 19, 2109 to May 25, 2109.