Week numbers 309
309 has 52 ISO weeks. Week 1: Jan 4 – 10 · Week 52: Dec 27, 309 – Jan 2, 310
309 at a glance
| Weeks in 309 | 52 |
|---|---|
| Week 1 | January 4, 309 – January 10, 309 |
| Week 52 | December 27, 309 – January 2, 310 |
| Days in 309 | 365 |
| Leap year | No |
All Weeks in 309
| Week | From | To | Month |
|---|---|---|---|
| Week 1 in 309 | January 4, 309 | January 10, 309 | January |
| Week 2 in 309 | January 11, 309 | January 17, 309 | January |
| Week 3 in 309 | January 18, 309 | January 24, 309 | January |
| Week 4 in 309 | January 25, 309 | January 31, 309 | January |
| Week 5 in 309 | February 1, 309 | February 7, 309 | February |
| Week 6 in 309 | February 8, 309 | February 14, 309 | February |
| Week 7 in 309 | February 15, 309 | February 21, 309 | February |
| Week 8 in 309 | February 22, 309 | February 28, 309 | February |
| Week 9 in 309 | March 1, 309 | March 7, 309 | March |
| Week 10 in 309 | March 8, 309 | March 14, 309 | March |
| Week 11 in 309 | March 15, 309 | March 21, 309 | March |
| Week 12 in 309 | March 22, 309 | March 28, 309 | March |
| Week 13 in 309 | March 29, 309 | April 4, 309 | March / April |
| Week 14 in 309 | April 5, 309 | April 11, 309 | April |
| Week 15 in 309 | April 12, 309 | April 18, 309 | April |
| Week 16 in 309 | April 19, 309 | April 25, 309 | April |
| Week 17 in 309 | April 26, 309 | May 2, 309 | April / May |
| Week 18 in 309 | May 3, 309 | May 9, 309 | May |
| Week 19 in 309 | May 10, 309 | May 16, 309 | May |
| Week 20 in 309 | May 17, 309 | May 23, 309 | May |
| Week 21 in 309 | May 24, 309 | May 30, 309 | May |
| Week 22 in 309 | May 31, 309 | June 6, 309 | May / June |
| Week 23 in 309 | June 7, 309 | June 13, 309 | June |
| Week 24 in 309 | June 14, 309 | June 20, 309 | June |
| Week 25 in 309 | June 21, 309 | June 27, 309 | June |
| Week 26 in 309 | June 28, 309 | July 4, 309 | June / July |
| Week 27 in 309 | July 5, 309 | July 11, 309 | July |
| Week 28 in 309 | July 12, 309 | July 18, 309 | July |
| Week 29 in 309 | July 19, 309 | July 25, 309 | July |
| Week 30 in 309 | July 26, 309 | August 1, 309 | July / August |
| Week 31 in 309 | August 2, 309 | August 8, 309 | August |
| Week 32 in 309 | August 9, 309 | August 15, 309 | August |
| Week 33 in 309 | August 16, 309 | August 22, 309 | August |
| Week 34 in 309 | August 23, 309 | August 29, 309 | August |
| Week 35 in 309 | August 30, 309 | September 5, 309 | August / September |
| Week 36 in 309 | September 6, 309 | September 12, 309 | September |
| Week 37 in 309 | September 13, 309 | September 19, 309 | September |
| Week 38 in 309 | September 20, 309 | September 26, 309 | September |
| Week 39 in 309 | September 27, 309 | October 3, 309 | September / October |
| Week 40 in 309 | October 4, 309 | October 10, 309 | October |
| Week 41 in 309 | October 11, 309 | October 17, 309 | October |
| Week 42 in 309 | October 18, 309 | October 24, 309 | October |
| Week 43 in 309 | October 25, 309 | October 31, 309 | October |
| Week 44 in 309 | November 1, 309 | November 7, 309 | November |
| Week 45 in 309 | November 8, 309 | November 14, 309 | November |
| Week 46 in 309 | November 15, 309 | November 21, 309 | November |
| Week 47 in 309 | November 22, 309 | November 28, 309 | November |
| Week 48 in 309 | November 29, 309 | December 5, 309 | November / December |
| Week 49 in 309 | December 6, 309 | December 12, 309 | December |
| Week 50 in 309 | December 13, 309 | December 19, 309 | December |
| Week 51 in 309 | December 20, 309 | December 26, 309 | December |
| Week 52 in 309 | December 27, 309 | January 2, 310 | December / January |
Calendars 309
| January 309 | |||||||
|---|---|---|---|---|---|---|---|
| Mo | Tu | We | Th | Fr | Sa | Su | |
| Week 53 | 1 | 2 | 3 | ||||
| Week 1 | 4 | 5 | 6 | 7 | 8 | 9 | 10 |
| Week 2 | 11 | 12 | 13 | 14 | 15 | 16 | 17 |
| Week 3 | 18 | 19 | 20 | 21 | 22 | 23 | 24 |
| Week 4 | 25 | 26 | 27 | 28 | 29 | 30 | 31 |
| February 309 | |||||||
|---|---|---|---|---|---|---|---|
| Mo | Tu | We | Th | Fr | Sa | Su | |
| Week 5 | 1 | 2 | 3 | 4 | 5 | 6 | 7 |
| Week 6 | 8 | 9 | 10 | 11 | 12 | 13 | 14 |
| Week 7 | 15 | 16 | 17 | 18 | 19 | 20 | 21 |
| Week 8 | 22 | 23 | 24 | 25 | 26 | 27 | 28 |
| March 309 | |||||||
|---|---|---|---|---|---|---|---|
| Mo | Tu | We | Th | Fr | Sa | Su | |
| Week 9 | 1 | 2 | 3 | 4 | 5 | 6 | 7 |
| Week 10 | 8 | 9 | 10 | 11 | 12 | 13 | 14 |
| Week 11 | 15 | 16 | 17 | 18 | 19 | 20 | 21 |
| Week 12 | 22 | 23 | 24 | 25 | 26 | 27 | 28 |
| Week 13 | 29 | 30 | 31 | ||||
| April 309 | |||||||
|---|---|---|---|---|---|---|---|
| Mo | Tu | We | Th | Fr | Sa | Su | |
| Week 13 | 1 | 2 | 3 | 4 | |||
| Week 14 | 5 | 6 | 7 | 8 | 9 | 10 | 11 |
| Week 15 | 12 | 13 | 14 | 15 | 16 | 17 | 18 |
| Week 16 | 19 | 20 | 21 | 22 | 23 | 24 | 25 |
| Week 17 | 26 | 27 | 28 | 29 | 30 | ||
| May 309 | |||||||
|---|---|---|---|---|---|---|---|
| Mo | Tu | We | Th | Fr | Sa | Su | |
| Week 17 | 1 | 2 | |||||
| Week 18 | 3 | 4 | 5 | 6 | 7 | 8 | 9 |
| Week 19 | 10 | 11 | 12 | 13 | 14 | 15 | 16 |
| Week 20 | 17 | 18 | 19 | 20 | 21 | 22 | 23 |
| Week 21 | 24 | 25 | 26 | 27 | 28 | 29 | 30 |
| Week 22 | 31 | ||||||
| June 309 | |||||||
|---|---|---|---|---|---|---|---|
| Mo | Tu | We | Th | Fr | Sa | Su | |
| Week 22 | 1 | 2 | 3 | 4 | 5 | 6 | |
| Week 23 | 7 | 8 | 9 | 10 | 11 | 12 | 13 |
| Week 24 | 14 | 15 | 16 | 17 | 18 | 19 | 20 |
| Week 25 | 21 | 22 | 23 | 24 | 25 | 26 | 27 |
| Week 26 | 28 | 29 | 30 | ||||
| July 309 | |||||||
|---|---|---|---|---|---|---|---|
| Mo | Tu | We | Th | Fr | Sa | Su | |
| Week 26 | 1 | 2 | 3 | 4 | |||
| Week 27 | 5 | 6 | 7 | 8 | 9 | 10 | 11 |
| Week 28 | 12 | 13 | 14 | 15 | 16 | 17 | 18 |
| Week 29 | 19 | 20 | 21 | 22 | 23 | 24 | 25 |
| Week 30 | 26 | 27 | 28 | 29 | 30 | 31 | |
| August 309 | |||||||
|---|---|---|---|---|---|---|---|
| Mo | Tu | We | Th | Fr | Sa | Su | |
| Week 30 | 1 | ||||||
| Week 31 | 2 | 3 | 4 | 5 | 6 | 7 | 8 |
| Week 32 | 9 | 10 | 11 | 12 | 13 | 14 | 15 |
| Week 33 | 16 | 17 | 18 | 19 | 20 | 21 | 22 |
| Week 34 | 23 | 24 | 25 | 26 | 27 | 28 | 29 |
| Week 35 | 30 | 31 | |||||
| September 309 | |||||||
|---|---|---|---|---|---|---|---|
| Mo | Tu | We | Th | Fr | Sa | Su | |
| Week 35 | 1 | 2 | 3 | 4 | 5 | ||
| Week 36 | 6 | 7 | 8 | 9 | 10 | 11 | 12 |
| Week 37 | 13 | 14 | 15 | 16 | 17 | 18 | 19 |
| Week 38 | 20 | 21 | 22 | 23 | 24 | 25 | 26 |
| Week 39 | 27 | 28 | 29 | 30 | |||
| October 309 | |||||||
|---|---|---|---|---|---|---|---|
| Mo | Tu | We | Th | Fr | Sa | Su | |
| Week 39 | 1 | 2 | 3 | ||||
| Week 40 | 4 | 5 | 6 | 7 | 8 | 9 | 10 |
| Week 41 | 11 | 12 | 13 | 14 | 15 | 16 | 17 |
| Week 42 | 18 | 19 | 20 | 21 | 22 | 23 | 24 |
| Week 43 | 25 | 26 | 27 | 28 | 29 | 30 | 31 |
Find the week number of a date
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 309 starts on January 4, 309 and ends on January 10, 309 (ISO 8601, Monday to Sunday). 309 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)
How many weeks does 309 have?
309 has 52 ISO weeks.
When does week 1 of 309 start?
Week 1 of 309 starts on January 4, 309 and ends on January 10, 309 (ISO 8601, Monday to Sunday).
When does the last week of 309 end?
Week 52 of 309 starts on December 27, 309 and ends on January 2, 310 (ISO 8601, Monday to Sunday).
Which years have 53 weeks?
The next years with 53 ISO weeks are 314, 320, 325, 331, 336.
Why do the US and Europe show different week numbers?
Europe follows ISO 8601: weeks start on Monday and week 1 is the week with the first Thursday of the year. In the US, weeks usually start on Sunday and week 1 is the week that contains 1 January, so the two numbers can differ by one.