Week numbers 2109

2109 has 52 ISO weeks. Week 1 of 2109 starts on December 31, 2108 and ends on January 6, 2109 (ISO 8601, Monday to Sunday).

2109 at a glance

Weeks in 210952
Week 1December 31, 2108 – January 6, 2109
Week 52December 23, 2109 – December 29, 2109
Days in 2109365
Leap yearNo

All Weeks in 2109

Week From To Month
Week 1 in 2109 December 31, 2108 January 6, 2109 December / January
Week 2 in 2109 January 7, 2109 January 13, 2109 January
Week 3 in 2109 January 14, 2109 January 20, 2109 January
Week 4 in 2109 January 21, 2109 January 27, 2109 January
Week 5 in 2109 January 28, 2109 February 3, 2109 January / February
Week 6 in 2109 February 4, 2109 February 10, 2109 February
Week 7 in 2109 February 11, 2109 February 17, 2109 February
Week 8 in 2109 February 18, 2109 February 24, 2109 February
Week 9 in 2109 February 25, 2109 March 3, 2109 February / March
Week 10 in 2109 March 4, 2109 March 10, 2109 March
Week 11 in 2109 March 11, 2109 March 17, 2109 March
Week 12 in 2109 March 18, 2109 March 24, 2109 March
Week 13 in 2109 March 25, 2109 March 31, 2109 March
Week 14 in 2109 April 1, 2109 April 7, 2109 April
Week 15 in 2109 April 8, 2109 April 14, 2109 April
Week 16 in 2109 April 15, 2109 April 21, 2109 April
Week 17 in 2109 April 22, 2109 April 28, 2109 April
Week 18 in 2109 April 29, 2109 May 5, 2109 April / May
Week 19 in 2109 May 6, 2109 May 12, 2109 May
Week 20 in 2109 May 13, 2109 May 19, 2109 May
Week 21 in 2109 May 20, 2109 May 26, 2109 May
Week 22 in 2109 May 27, 2109 June 2, 2109 May / June
Week 23 in 2109 June 3, 2109 June 9, 2109 June
Week 24 in 2109 June 10, 2109 June 16, 2109 June
Week 25 in 2109 June 17, 2109 June 23, 2109 June
Week 26 in 2109 June 24, 2109 June 30, 2109 June
Week 27 in 2109 July 1, 2109 July 7, 2109 July
Week 28 in 2109 July 8, 2109 July 14, 2109 July
Week 29 in 2109 July 15, 2109 July 21, 2109 July
Week 30 in 2109 July 22, 2109 July 28, 2109 July
Week 31 in 2109 July 29, 2109 August 4, 2109 July / August
Week 32 in 2109 August 5, 2109 August 11, 2109 August
Week 33 in 2109 August 12, 2109 August 18, 2109 August
Week 34 in 2109 August 19, 2109 August 25, 2109 August
Week 35 in 2109 August 26, 2109 September 1, 2109 August / September
Week 36 in 2109 September 2, 2109 September 8, 2109 September
Week 37 in 2109 September 9, 2109 September 15, 2109 September
Week 38 in 2109 September 16, 2109 September 22, 2109 September
Week 39 in 2109 September 23, 2109 September 29, 2109 September
Week 40 in 2109 September 30, 2109 October 6, 2109 September / October
Week 41 in 2109 October 7, 2109 October 13, 2109 October
Week 42 in 2109 October 14, 2109 October 20, 2109 October
Week 43 in 2109 October 21, 2109 October 27, 2109 October
Week 44 in 2109 October 28, 2109 November 3, 2109 October / November
Week 45 in 2109 November 4, 2109 November 10, 2109 November
Week 46 in 2109 November 11, 2109 November 17, 2109 November
Week 47 in 2109 November 18, 2109 November 24, 2109 November
Week 48 in 2109 November 25, 2109 December 1, 2109 November / December
Week 49 in 2109 December 2, 2109 December 8, 2109 December
Week 50 in 2109 December 9, 2109 December 15, 2109 December
Week 51 in 2109 December 16, 2109 December 22, 2109 December
Week 52 in 2109 December 23, 2109 December 29, 2109 December

Calendars 2109

January 2109
MoTuWeThFrSaSu
Week 1123456
Week 278910111213
Week 314151617181920
Week 421222324252627
Week 528293031
February 2109
MoTuWeThFrSaSu
Week 5123
Week 645678910
Week 711121314151617
Week 818192021222324
Week 925262728
March 2109
MoTuWeThFrSaSu
Week 9123
Week 1045678910
Week 1111121314151617
Week 1218192021222324
Week 1325262728293031
April 2109
MoTuWeThFrSaSu
Week 141234567
Week 15891011121314
Week 1615161718192021
Week 1722232425262728
Week 182930
May 2109
MoTuWeThFrSaSu
Week 1812345
Week 196789101112
Week 2013141516171819
Week 2120212223242526
Week 222728293031
June 2109
MoTuWeThFrSaSu
Week 2212
Week 233456789
Week 2410111213141516
Week 2517181920212223
Week 2624252627282930
July 2109
MoTuWeThFrSaSu
Week 271234567
Week 28891011121314
Week 2915161718192021
Week 3022232425262728
Week 31293031
August 2109
MoTuWeThFrSaSu
Week 311234
Week 32567891011
Week 3312131415161718
Week 3419202122232425
Week 35262728293031
September 2109
MoTuWeThFrSaSu
Week 351
Week 362345678
Week 379101112131415
Week 3816171819202122
Week 3923242526272829
Week 4030
October 2109
MoTuWeThFrSaSu
Week 40123456
Week 4178910111213
Week 4214151617181920
Week 4321222324252627
Week 4428293031
November 2109
MoTuWeThFrSaSu
Week 44123
Week 4545678910
Week 4611121314151617
Week 4718192021222324
Week 48252627282930
December 2109
MoTuWeThFrSaSu
Week 21
Week 492345678
Week 509101112131415
Week 5116171819202122
Week 5223242526272829
Week 13031

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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 2109 starts on December 31, 2108 and ends on January 6, 2109 (ISO 8601, Monday to Sunday). 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)

How many weeks does 2109 have?

2109 has 52 ISO weeks.

When does week 1 of 2109 start?

Week 1 of 2109 starts on December 31, 2108 and ends on January 6, 2109 (ISO 8601, Monday to Sunday).

When does the last week of 2109 end?

Week 52 of 2109 starts on December 23, 2109 and ends on December 29, 2109 (ISO 8601, Monday to Sunday).

Which years have 53 weeks?

The next years with 53 ISO weeks are 2111, 2116, 2122, 2128, 2133.

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.