Week numbers 1840

1840 has 53 ISO weeks, because it is a leap year that starts on a Wednesday. Week 1 of 1840 starts on December 30, 1839 and ends on January 5, 1840 (ISO 8601, Monday to Sunday).

1840 at a glance

Weeks in 184053
Week 1December 30, 1839 – January 5, 1840
Week 53December 28, 1840 – January 3, 1841
Days in 1840366
Leap yearYes

All Weeks in 1840

Week From To Month
Week 1 in 1840 December 30, 1839 January 5, 1840 December / January
Week 2 in 1840 January 6, 1840 January 12, 1840 January
Week 3 in 1840 January 13, 1840 January 19, 1840 January
Week 4 in 1840 January 20, 1840 January 26, 1840 January
Week 5 in 1840 January 27, 1840 February 2, 1840 January / February
Week 6 in 1840 February 3, 1840 February 9, 1840 February
Week 7 in 1840 February 10, 1840 February 16, 1840 February
Week 8 in 1840 February 17, 1840 February 23, 1840 February
Week 9 in 1840 February 24, 1840 March 1, 1840 February / March
Week 10 in 1840 March 2, 1840 March 8, 1840 March
Week 11 in 1840 March 9, 1840 March 15, 1840 March
Week 12 in 1840 March 16, 1840 March 22, 1840 March
Week 13 in 1840 March 23, 1840 March 29, 1840 March
Week 14 in 1840 March 30, 1840 April 5, 1840 March / April
Week 15 in 1840 April 6, 1840 April 12, 1840 April
Week 16 in 1840 April 13, 1840 April 19, 1840 April
Week 17 in 1840 April 20, 1840 April 26, 1840 April
Week 18 in 1840 April 27, 1840 May 3, 1840 April / May
Week 19 in 1840 May 4, 1840 May 10, 1840 May
Week 20 in 1840 May 11, 1840 May 17, 1840 May
Week 21 in 1840 May 18, 1840 May 24, 1840 May
Week 22 in 1840 May 25, 1840 May 31, 1840 May
Week 23 in 1840 June 1, 1840 June 7, 1840 June
Week 24 in 1840 June 8, 1840 June 14, 1840 June
Week 25 in 1840 June 15, 1840 June 21, 1840 June
Week 26 in 1840 June 22, 1840 June 28, 1840 June
Week 27 in 1840 June 29, 1840 July 5, 1840 June / July
Week 28 in 1840 July 6, 1840 July 12, 1840 July
Week 29 in 1840 July 13, 1840 July 19, 1840 July
Week 30 in 1840 July 20, 1840 July 26, 1840 July
Week 31 in 1840 July 27, 1840 August 2, 1840 July / August
Week 32 in 1840 August 3, 1840 August 9, 1840 August
Week 33 in 1840 August 10, 1840 August 16, 1840 August
Week 34 in 1840 August 17, 1840 August 23, 1840 August
Week 35 in 1840 August 24, 1840 August 30, 1840 August
Week 36 in 1840 August 31, 1840 September 6, 1840 August / September
Week 37 in 1840 September 7, 1840 September 13, 1840 September
Week 38 in 1840 September 14, 1840 September 20, 1840 September
Week 39 in 1840 September 21, 1840 September 27, 1840 September
Week 40 in 1840 September 28, 1840 October 4, 1840 September / October
Week 41 in 1840 October 5, 1840 October 11, 1840 October
Week 42 in 1840 October 12, 1840 October 18, 1840 October
Week 43 in 1840 October 19, 1840 October 25, 1840 October
Week 44 in 1840 October 26, 1840 November 1, 1840 October / November
Week 45 in 1840 November 2, 1840 November 8, 1840 November
Week 46 in 1840 November 9, 1840 November 15, 1840 November
Week 47 in 1840 November 16, 1840 November 22, 1840 November
Week 48 in 1840 November 23, 1840 November 29, 1840 November
Week 49 in 1840 November 30, 1840 December 6, 1840 November / December
Week 50 in 1840 December 7, 1840 December 13, 1840 December
Week 51 in 1840 December 14, 1840 December 20, 1840 December
Week 52 in 1840 December 21, 1840 December 27, 1840 December
Week 53 in 1840 December 28, 1840 January 3, 1841 December / January

Calendars 1840

January 1840
MoTuWeThFrSaSu
Week 112345
Week 26789101112
Week 313141516171819
Week 420212223242526
Week 52728293031
February 1840
MoTuWeThFrSaSu
Week 512
Week 63456789
Week 710111213141516
Week 817181920212223
Week 9242526272829
March 1840
MoTuWeThFrSaSu
Week 91
Week 102345678
Week 119101112131415
Week 1216171819202122
Week 1323242526272829
Week 143031
April 1840
MoTuWeThFrSaSu
Week 1412345
Week 156789101112
Week 1613141516171819
Week 1720212223242526
Week 1827282930
May 1840
MoTuWeThFrSaSu
Week 18123
Week 1945678910
Week 2011121314151617
Week 2118192021222324
Week 2225262728293031
June 1840
MoTuWeThFrSaSu
Week 231234567
Week 24891011121314
Week 2515161718192021
Week 2622232425262728
Week 272930
July 1840
MoTuWeThFrSaSu
Week 2712345
Week 286789101112
Week 2913141516171819
Week 3020212223242526
Week 312728293031
August 1840
MoTuWeThFrSaSu
Week 3112
Week 323456789
Week 3310111213141516
Week 3417181920212223
Week 3524252627282930
Week 3631
September 1840
MoTuWeThFrSaSu
Week 36123456
Week 3778910111213
Week 3814151617181920
Week 3921222324252627
Week 40282930
October 1840
MoTuWeThFrSaSu
Week 401234
Week 41567891011
Week 4212131415161718
Week 4319202122232425
Week 44262728293031
November 1840
MoTuWeThFrSaSu
Week 441
Week 452345678
Week 469101112131415
Week 4716171819202122
Week 4823242526272829
Week 4930
December 1840
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 1840 starts on December 30, 1839 and ends on January 5, 1840 (ISO 8601, Monday to Sunday). 1840 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 1840 have?

1840 has 53 ISO weeks, because it is a leap year that starts on a Wednesday.

When does week 1 of 1840 start?

Week 1 of 1840 starts on December 30, 1839 and ends on January 5, 1840 (ISO 8601, Monday to Sunday).

When does the last week of 1840 end?

Week 53 of 1840 starts on December 28, 1840 and ends on January 3, 1841 (ISO 8601, Monday to Sunday).

Which years have 53 weeks?

The next years with 53 ISO weeks are 1840, 1846, 1852, 1857, 1863.

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.