Week numbers 2004

2004 has 53 ISO weeks, because 1 January 2004 falls on a Thursday. Week 1: Dec 29, 2003 – Jan 4, 2004 · Week 53: Dec 27, 2004 – Jan 2, 2005

2004 at a glance

Weeks in 200453
Week 1December 29, 2003 – January 4, 2004
Week 53December 27, 2004 – January 2, 2005
Days in 2004366
Leap yearYes

All Weeks in 2004

Week From To Month
Week 1 in 2004 December 29, 2003 January 4, 2004 December / January
Week 2 in 2004 January 5, 2004 January 11, 2004 January
Week 3 in 2004 January 12, 2004 January 18, 2004 January
Week 4 in 2004 January 19, 2004 January 25, 2004 January
Week 5 in 2004 January 26, 2004 February 1, 2004 January / February
Week 6 in 2004 February 2, 2004 February 8, 2004 February
Week 7 in 2004 February 9, 2004 February 15, 2004 February
Week 8 in 2004 February 16, 2004 February 22, 2004 February
Week 9 in 2004 February 23, 2004 February 29, 2004 February
Week 10 in 2004 March 1, 2004 March 7, 2004 March
Week 11 in 2004 March 8, 2004 March 14, 2004 March
Week 12 in 2004 March 15, 2004 March 21, 2004 March
Week 13 in 2004 March 22, 2004 March 28, 2004 March
Week 14 in 2004 March 29, 2004 April 4, 2004 March / April
Week 15 in 2004 April 5, 2004 April 11, 2004 April
Week 16 in 2004 April 12, 2004 April 18, 2004 April
Week 17 in 2004 April 19, 2004 April 25, 2004 April
Week 18 in 2004 April 26, 2004 May 2, 2004 April / May
Week 19 in 2004 May 3, 2004 May 9, 2004 May
Week 20 in 2004 May 10, 2004 May 16, 2004 May
Week 21 in 2004 May 17, 2004 May 23, 2004 May
Week 22 in 2004 May 24, 2004 May 30, 2004 May
Week 23 in 2004 May 31, 2004 June 6, 2004 May / June
Week 24 in 2004 June 7, 2004 June 13, 2004 June
Week 25 in 2004 June 14, 2004 June 20, 2004 June
Week 26 in 2004 June 21, 2004 June 27, 2004 June
Week 27 in 2004 June 28, 2004 July 4, 2004 June / July
Week 28 in 2004 July 5, 2004 July 11, 2004 July
Week 29 in 2004 July 12, 2004 July 18, 2004 July
Week 30 in 2004 July 19, 2004 July 25, 2004 July
Week 31 in 2004 July 26, 2004 August 1, 2004 July / August
Week 32 in 2004 August 2, 2004 August 8, 2004 August
Week 33 in 2004 August 9, 2004 August 15, 2004 August
Week 34 in 2004 August 16, 2004 August 22, 2004 August
Week 35 in 2004 August 23, 2004 August 29, 2004 August
Week 36 in 2004 August 30, 2004 September 5, 2004 August / September
Week 37 in 2004 September 6, 2004 September 12, 2004 September
Week 38 in 2004 September 13, 2004 September 19, 2004 September
Week 39 in 2004 September 20, 2004 September 26, 2004 September
Week 40 in 2004 September 27, 2004 October 3, 2004 September / October
Week 41 in 2004 October 4, 2004 October 10, 2004 October
Week 42 in 2004 October 11, 2004 October 17, 2004 October
Week 43 in 2004 October 18, 2004 October 24, 2004 October
Week 44 in 2004 October 25, 2004 October 31, 2004 October
Week 45 in 2004 November 1, 2004 November 7, 2004 November
Week 46 in 2004 November 8, 2004 November 14, 2004 November
Week 47 in 2004 November 15, 2004 November 21, 2004 November
Week 48 in 2004 November 22, 2004 November 28, 2004 November
Week 49 in 2004 November 29, 2004 December 5, 2004 November / December
Week 50 in 2004 December 6, 2004 December 12, 2004 December
Week 51 in 2004 December 13, 2004 December 19, 2004 December
Week 52 in 2004 December 20, 2004 December 26, 2004 December
Week 53 in 2004 December 27, 2004 January 2, 2005 December / January

Calendars 2004

January 2004
MoTuWeThFrSaSu
Week 11234
Week 2567891011
Week 312131415161718
Week 419202122232425
Week 5262728293031
February 2004
MoTuWeThFrSaSu
Week 51
Week 62345678
Week 79101112131415
Week 816171819202122
Week 923242526272829
March 2004
MoTuWeThFrSaSu
Week 101234567
Week 11891011121314
Week 1215161718192021
Week 1322232425262728
Week 14293031
April 2004
MoTuWeThFrSaSu
Week 141234
Week 15567891011
Week 1612131415161718
Week 1719202122232425
Week 182627282930
May 2004
MoTuWeThFrSaSu
Week 1812
Week 193456789
Week 2010111213141516
Week 2117181920212223
Week 2224252627282930
Week 2331
June 2004
MoTuWeThFrSaSu
Week 23123456
Week 2478910111213
Week 2514151617181920
Week 2621222324252627
Week 27282930
July 2004
MoTuWeThFrSaSu
Week 271234
Week 28567891011
Week 2912131415161718
Week 3019202122232425
Week 31262728293031
August 2004
MoTuWeThFrSaSu
Week 311
Week 322345678
Week 339101112131415
Week 3416171819202122
Week 3523242526272829
Week 363031
September 2004
MoTuWeThFrSaSu
Week 3612345
Week 376789101112
Week 3813141516171819
Week 3920212223242526
Week 4027282930
October 2004
MoTuWeThFrSaSu
Week 40123
Week 4145678910
Week 4211121314151617
Week 4318192021222324
Week 4425262728293031
November 2004
MoTuWeThFrSaSu
Week 451234567
Week 46891011121314
Week 4715161718192021
Week 4822232425262728
Week 492930
December 2004
MoTuWeThFrSaSu
Week 212345
Week 506789101112
Week 5113141516171819
Week 5220212223242526
Week 532728293031

Download Calendar in printable A4 PDF

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 2004 starts on December 29, 2003 and ends on January 4, 2004 (ISO 8601, Monday to Sunday). 2004 has 53 ISO weeks, because 1 January 2004 falls on a Thursday.

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 2004 have?

2004 has 53 ISO weeks, because 1 January 2004 falls on a Thursday.

When does week 1 of 2004 start?

Week 1 of 2004 starts on December 29, 2003 and ends on January 4, 2004 (ISO 8601, Monday to Sunday).

When does the last week of 2004 end?

Week 53 of 2004 starts on December 27, 2004 and ends on January 2, 2005 (ISO 8601, Monday to Sunday).

Which years have 53 weeks?

The next years with 53 ISO weeks are 2004, 2009, 2015, 2020, 2026.

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.