Week Number Calculator

Calendar weeks 2026 - CW 2026

Week Numbers ﹣ Calendar weeks 2026

The following table shows all ISO calendar weeks 2026 from 1 to 53, with their start date beginning on Monday and their end date falling on Sunday.

European and Asian ISO calendar weeks 2026 - CW 2026
CW Mo Tu We Th Fr Sa SuISO-Name
CW 1 29/12 30/12 31/12 01/01 02/01 03/01 04/012026‑W01
CW 2 05/01 06/01 07/01 08/01 09/01 10/01 11/012026‑W02
CW 3 12/01 13/01 14/01 15/01 16/01 17/01 18/012026‑W03
CW 4 19/01 20/01 21/01 22/01 23/01 24/01 25/012026‑W04
CW 5 26/01 27/01 28/01 29/01 30/01 31/01 01/022026‑W05
CW 6 02/02 03/02 04/02 05/02 06/02 07/02 08/022026‑W06
CW 7 09/02 10/02 11/02 12/02 13/02 14/02 15/022026‑W07
CW 8 16/02 17/02 18/02 19/02 20/02 21/02 22/022026‑W08
CW 9 23/02 24/02 25/02 26/02 27/02 28/02 01/032026‑W09
CW 10 02/03 03/03 04/03 05/03 06/03 07/03 08/032026‑W10
CW 11 09/03 10/03 11/03 12/03 13/03 14/03 15/032026‑W11
CW 12 16/03 17/03 18/03 19/03 20/03 21/03 22/032026‑W12
CW 13 23/03 24/03 25/03 26/03 27/03 28/03 29/032026‑W13
CW 14 30/03 31/03 01/04 02/04 03/04 04/04 05/042026‑W14
CW 15 06/04 07/04 08/04 09/04 10/04 11/04 12/042026‑W15
CW 16 13/04 14/04 15/04 16/04 17/04 18/04 19/042026‑W16
CW 17 20/04 21/04 22/04 23/04 24/04 25/04 26/042026‑W17
CW 18 27/04 28/04 29/04 30/04 01/05 02/05 03/052026‑W18
CW 19 04/05 05/05 06/05 07/05 08/05 09/05 10/052026‑W19
CW 20 11/05 12/05 13/05 14/05 15/05 16/05 17/052026‑W20
CW 21 18/05 19/05 20/05 21/05 22/05 23/05 24/052026‑W21
CW 22 25/05 26/05 27/05 28/05 29/05 30/05 31/052026‑W22
CW 23 01/06 02/06 03/06 04/06 05/06 06/06 07/062026‑W23
CW 24 08/06 09/06 10/06 11/06 12/06 13/06 14/062026‑W24
CW 25 15/06 16/06 17/06 18/06 19/06 20/06 21/062026‑W25
CW 26 22/06 23/06 24/06 25/06 26/06 27/06 28/062026‑W26
CW 27 29/06 30/06 01/07 02/07 03/07 04/07 05/072026‑W27
CW 28 06/07 07/07 08/07 09/07 10/07 11/07 12/072026‑W28
CW 29 13/07 14/07 15/07 16/07 17/07 18/07 19/072026‑W29
CW 30 20/07 21/07 22/07 23/07 24/07 25/07 26/072026‑W30
CW 31 27/07 28/07 29/07 30/07 31/07 01/08 02/082026‑W31
CW 32 03/08 04/08 05/08 06/08 07/08 08/08 09/082026‑W32
CW 33 10/08 11/08 12/08 13/08 14/08 15/08 16/082026‑W33
CW 34 17/08 18/08 19/08 20/08 21/08 22/08 23/082026‑W34
CW 35 24/08 25/08 26/08 27/08 28/08 29/08 30/082026‑W35
CW 36 31/08 01/09 02/09 03/09 04/09 05/09 06/092026‑W36
CW 37 07/09 08/09 09/09 10/09 11/09 12/09 13/092026‑W37
CW 38 14/09 15/09 16/09 17/09 18/09 19/09 20/092026‑W38
CW 39 21/09 22/09 23/09 24/09 25/09 26/09 27/092026‑W39
CW 40 28/09 29/09 30/09 01/10 02/10 03/10 04/102026‑W40
CW 41 05/10 06/10 07/10 08/10 09/10 10/10 11/102026‑W41
CW 42 12/10 13/10 14/10 15/10 16/10 17/10 18/102026‑W42
CW 43 19/10 20/10 21/10 22/10 23/10 24/10 25/102026‑W43
CW 44 26/10 27/10 28/10 29/10 30/10 31/10 01/112026‑W44
CW 45 02/11 03/11 04/11 05/11 06/11 07/11 08/112026‑W45
CW 46 09/11 10/11 11/11 12/11 13/11 14/11 15/112026‑W46
CW 47 16/11 17/11 18/11 19/11 20/11 21/11 22/112026‑W47
CW 48 23/11 24/11 25/11 26/11 27/11 28/11 29/112026‑W48
CW 49 30/11 01/12 02/12 03/12 04/12 05/12 06/122026‑W49
CW 50 07/12 08/12 09/12 10/12 11/12 12/12 13/122026‑W50
CW 51 14/12 15/12 16/12 17/12 18/12 19/12 20/122026‑W51
CW 52 21/12 22/12 23/12 24/12 25/12 26/12 27/122026‑W52
CW 53 28/12 29/12 30/12 31/12 01/01 02/01 03/012026‑W53

The ISO calendar weeks for 2026 are defined according to the international ISO standard. That is, each calendar week starts on Monday and ends on Sunday. Even during the change of year, a new calendar week starts on Monday and ends on Sunday. The ISO standard specifies that the majority of the first calendar week (i.e., at least four days) must lie in the new year.

Table of all American calendar weeks for 2026

The following table shows all "American" calendar weeks 2026, with their start date beginning on Sunday and their end date falling on Saturday.

American calendar weeks 2026 - CW 2026
CW Su Mo Tu We Th Fr Sa
CW 101/0102/0103/01
CW 2 04/01 05/01 06/01 07/01 08/01 09/01 10/01
CW 3 11/01 12/01 13/01 14/01 15/01 16/01 17/01
CW 4 18/01 19/01 20/01 21/01 22/01 23/01 24/01
CW 5 25/01 26/01 27/01 28/01 29/01 30/01 31/01
CW 6 01/02 02/02 03/02 04/02 05/02 06/02 07/02
CW 7 08/02 09/02 10/02 11/02 12/02 13/02 14/02
CW 8 15/02 16/02 17/02 18/02 19/02 20/02 21/02
CW 9 22/02 23/02 24/02 25/02 26/02 27/02 28/02
CW 10 01/03 02/03 03/03 04/03 05/03 06/03 07/03
CW 11 08/03 09/03 10/03 11/03 12/03 13/03 14/03
CW 12 15/03 16/03 17/03 18/03 19/03 20/03 21/03
CW 13 22/03 23/03 24/03 25/03 26/03 27/03 28/03
CW 14 29/03 30/03 31/03 01/04 02/04 03/04 04/04
CW 15 05/04 06/04 07/04 08/04 09/04 10/04 11/04
CW 16 12/04 13/04 14/04 15/04 16/04 17/04 18/04
CW 17 19/04 20/04 21/04 22/04 23/04 24/04 25/04
CW 18 26/04 27/04 28/04 29/04 30/04 01/05 02/05
CW 19 03/05 04/05 05/05 06/05 07/05 08/05 09/05
CW 20 10/05 11/05 12/05 13/05 14/05 15/05 16/05
CW 21 17/05 18/05 19/05 20/05 21/05 22/05 23/05
CW 22 24/05 25/05 26/05 27/05 28/05 29/05 30/05
CW 23 31/05 01/06 02/06 03/06 04/06 05/06 06/06
CW 24 07/06 08/06 09/06 10/06 11/06 12/06 13/06
CW 25 14/06 15/06 16/06 17/06 18/06 19/06 20/06
CW 26 21/06 22/06 23/06 24/06 25/06 26/06 27/06
CW 27 28/06 29/06 30/06 01/07 02/07 03/07 04/07
CW 28 05/07 06/07 07/07 08/07 09/07 10/07 11/07
CW 29 12/07 13/07 14/07 15/07 16/07 17/07 18/07
CW 30 19/07 20/07 21/07 22/07 23/07 24/07 25/07
CW 31 26/07 27/07 28/07 29/07 30/07 31/07 01/08
CW 32 02/08 03/08 04/08 05/08 06/08 07/08 08/08
CW 33 09/08 10/08 11/08 12/08 13/08 14/08 15/08
CW 34 16/08 17/08 18/08 19/08 20/08 21/08 22/08
CW 35 23/08 24/08 25/08 26/08 27/08 28/08 29/08
CW 36 30/08 31/08 01/09 02/09 03/09 04/09 05/09
CW 37 06/09 07/09 08/09 09/09 10/09 11/09 12/09
CW 38 13/09 14/09 15/09 16/09 17/09 18/09 19/09
CW 39 20/09 21/09 22/09 23/09 24/09 25/09 26/09
CW 40 27/09 28/09 29/09 30/09 01/10 02/10 03/10
CW 41 04/10 05/10 06/10 07/10 08/10 09/10 10/10
CW 42 11/10 12/10 13/10 14/10 15/10 16/10 17/10
CW 43 18/10 19/10 20/10 21/10 22/10 23/10 24/10
CW 44 25/10 25/10 26/10 27/10 28/10 29/10 30/10
CW 45 01/11 02/11 03/11 04/11 05/11 06/11 07/11
CW 46 08/11 09/11 10/11 11/11 12/11 13/11 14/11
CW 47 15/11 16/11 17/11 18/11 19/11 20/11 21/11
CW 48 22/11 23/11 24/11 25/11 26/11 27/11 28/11
CW 49 29/11 30/11 01/12 02/12 03/12 04/12 05/12
CW 50 06/12 07/12 08/12 09/12 10/12 11/12 12/12
CW 51 13/12 14/12 15/12 16/12 17/12 18/12 19/12
CW 52 20/12 21/12 22/12 23/12 24/12 25/12 26/12
CW 5327/1228/1229/1230/1231/12

The "American" calendar weeks for 2026 are used in the USA, Canada and most Latin American countries, Australia, Japan, Israel, South Korea and others. Unlike the otherwise internationally standardised ISO weeks, the American calendar weeks start on Sundays instead of Mondays and end on Saturdays. However, the first calendar week always begins on the 1st of January and the last always ends on the 31st of December. These two weeks can have fewer than seven days. There are always 53 calendar weeks, except in a leap year where 31st December is a Sunday. As a result, such a year will have 54 calendar weeks.

Calculation of any calendar weeks 2026

Source information

As source for the information in the 'Week Numbers' category, we have used in particular:

Last update

This page of the 'Week Numbers' category was last edited or reviewed by Michael Mühl. It corresponds to the current status.

Changes in this category "Week Numbers"