Week numbers 172

172 has 53 ISO weeks, because it is a leap year that starts on a Wednesday. Week 1: Dec 30, 171 – Jan 5, 172 · Week 53: Dec 28, 172 – Jan 3, 173

172 at a glance

Weeks in 17253
Week 1December 30, 171 – January 5, 172
Week 53December 28, 172 – January 3, 173
Days in 172366
Leap yearYes

All Weeks in 172

Week From To Month
Week 1 in 172 December 30, 171 January 5, 172 December / January
Week 2 in 172 January 6, 172 January 12, 172 January
Week 3 in 172 January 13, 172 January 19, 172 January
Week 4 in 172 January 20, 172 January 26, 172 January
Week 5 in 172 January 27, 172 February 2, 172 January / February
Week 6 in 172 February 3, 172 February 9, 172 February
Week 7 in 172 February 10, 172 February 16, 172 February
Week 8 in 172 February 17, 172 February 23, 172 February
Week 9 in 172 February 24, 172 March 1, 172 February / March
Week 10 in 172 March 2, 172 March 8, 172 March
Week 11 in 172 March 9, 172 March 15, 172 March
Week 12 in 172 March 16, 172 March 22, 172 March
Week 13 in 172 March 23, 172 March 29, 172 March
Week 14 in 172 March 30, 172 April 5, 172 March / April
Week 15 in 172 April 6, 172 April 12, 172 April
Week 16 in 172 April 13, 172 April 19, 172 April
Week 17 in 172 April 20, 172 April 26, 172 April
Week 18 in 172 April 27, 172 May 3, 172 April / May
Week 19 in 172 May 4, 172 May 10, 172 May
Week 20 in 172 May 11, 172 May 17, 172 May
Week 21 in 172 May 18, 172 May 24, 172 May
Week 22 in 172 May 25, 172 May 31, 172 May
Week 23 in 172 June 1, 172 June 7, 172 June
Week 24 in 172 June 8, 172 June 14, 172 June
Week 25 in 172 June 15, 172 June 21, 172 June
Week 26 in 172 June 22, 172 June 28, 172 June
Week 27 in 172 June 29, 172 July 5, 172 June / July
Week 28 in 172 July 6, 172 July 12, 172 July
Week 29 in 172 July 13, 172 July 19, 172 July
Week 30 in 172 July 20, 172 July 26, 172 July
Week 31 in 172 July 27, 172 August 2, 172 July / August
Week 32 in 172 August 3, 172 August 9, 172 August
Week 33 in 172 August 10, 172 August 16, 172 August
Week 34 in 172 August 17, 172 August 23, 172 August
Week 35 in 172 August 24, 172 August 30, 172 August
Week 36 in 172 August 31, 172 September 6, 172 August / September
Week 37 in 172 September 7, 172 September 13, 172 September
Week 38 in 172 September 14, 172 September 20, 172 September
Week 39 in 172 September 21, 172 September 27, 172 September
Week 40 in 172 September 28, 172 October 4, 172 September / October
Week 41 in 172 October 5, 172 October 11, 172 October
Week 42 in 172 October 12, 172 October 18, 172 October
Week 43 in 172 October 19, 172 October 25, 172 October
Week 44 in 172 October 26, 172 November 1, 172 October / November
Week 45 in 172 November 2, 172 November 8, 172 November
Week 46 in 172 November 9, 172 November 15, 172 November
Week 47 in 172 November 16, 172 November 22, 172 November
Week 48 in 172 November 23, 172 November 29, 172 November
Week 49 in 172 November 30, 172 December 6, 172 November / December
Week 50 in 172 December 7, 172 December 13, 172 December
Week 51 in 172 December 14, 172 December 20, 172 December
Week 52 in 172 December 21, 172 December 27, 172 December
Week 53 in 172 December 28, 172 January 3, 173 December / January

Calendars 172

January 172
MoTuWeThFrSaSu
Week 112345
Week 26789101112
Week 313141516171819
Week 420212223242526
Week 52728293031
February 172
MoTuWeThFrSaSu
Week 512
Week 63456789
Week 710111213141516
Week 817181920212223
Week 9242526272829
March 172
MoTuWeThFrSaSu
Week 91
Week 102345678
Week 119101112131415
Week 1216171819202122
Week 1323242526272829
Week 143031
April 172
MoTuWeThFrSaSu
Week 1412345
Week 156789101112
Week 1613141516171819
Week 1720212223242526
Week 1827282930
May 172
MoTuWeThFrSaSu
Week 18123
Week 1945678910
Week 2011121314151617
Week 2118192021222324
Week 2225262728293031
June 172
MoTuWeThFrSaSu
Week 231234567
Week 24891011121314
Week 2515161718192021
Week 2622232425262728
Week 272930
July 172
MoTuWeThFrSaSu
Week 2712345
Week 286789101112
Week 2913141516171819
Week 3020212223242526
Week 312728293031
August 172
MoTuWeThFrSaSu
Week 3112
Week 323456789
Week 3310111213141516
Week 3417181920212223
Week 3524252627282930
Week 3631
September 172
MoTuWeThFrSaSu
Week 36123456
Week 3778910111213
Week 3814151617181920
Week 3921222324252627
Week 40282930
October 172
MoTuWeThFrSaSu
Week 401234
Week 41567891011
Week 4212131415161718
Week 4319202122232425
Week 44262728293031
November 172
MoTuWeThFrSaSu
Week 441
Week 452345678
Week 469101112131415
Week 4716171819202122
Week 4823242526272829
Week 4930
December 172
MoTuWeThFrSaSu
Week 2123456
Week 5078910111213
Week 5114151617181920
Week 5221222324252627
Week 5328293031

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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 172 starts on December 30, 171 and ends on January 5, 172 (ISO 8601, Monday to Sunday). 172 has 53 ISO weeks, because it is a leap year that starts on a Wednesday.

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 172 have?

172 has 53 ISO weeks, because it is a leap year that starts on a Wednesday.

When does week 1 of 172 start?

Week 1 of 172 starts on December 30, 171 and ends on January 5, 172 (ISO 8601, Monday to Sunday).

When does the last week of 172 end?

Week 53 of 172 starts on December 28, 172 and ends on January 3, 173 (ISO 8601, Monday to Sunday).

Which years have 53 weeks?

The next years with 53 ISO weeks are 172, 178, 184, 189, 195.

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.