Week numbers 1230

1230 has 52 ISO weeks. Week 1: Dec 31, 1229 – Jan 6, 1230 · Week 52: Dec 23 – 29

1230 at a glance

Weeks in 123052
Week 1December 31, 1229 – January 6, 1230
Week 52December 23, 1230 – December 29, 1230
Days in 1230365
Leap yearNo

All Weeks in 1230

Week From To Month
Week 1 in 1230 December 31, 1229 January 6, 1230 December / January
Week 2 in 1230 January 7, 1230 January 13, 1230 January
Week 3 in 1230 January 14, 1230 January 20, 1230 January
Week 4 in 1230 January 21, 1230 January 27, 1230 January
Week 5 in 1230 January 28, 1230 February 3, 1230 January / February
Week 6 in 1230 February 4, 1230 February 10, 1230 February
Week 7 in 1230 February 11, 1230 February 17, 1230 February
Week 8 in 1230 February 18, 1230 February 24, 1230 February
Week 9 in 1230 February 25, 1230 March 3, 1230 February / March
Week 10 in 1230 March 4, 1230 March 10, 1230 March
Week 11 in 1230 March 11, 1230 March 17, 1230 March
Week 12 in 1230 March 18, 1230 March 24, 1230 March
Week 13 in 1230 March 25, 1230 March 31, 1230 March
Week 14 in 1230 April 1, 1230 April 7, 1230 April
Week 15 in 1230 April 8, 1230 April 14, 1230 April
Week 16 in 1230 April 15, 1230 April 21, 1230 April
Week 17 in 1230 April 22, 1230 April 28, 1230 April
Week 18 in 1230 April 29, 1230 May 5, 1230 April / May
Week 19 in 1230 May 6, 1230 May 12, 1230 May
Week 20 in 1230 May 13, 1230 May 19, 1230 May
Week 21 in 1230 May 20, 1230 May 26, 1230 May
Week 22 in 1230 May 27, 1230 June 2, 1230 May / June
Week 23 in 1230 June 3, 1230 June 9, 1230 June
Week 24 in 1230 June 10, 1230 June 16, 1230 June
Week 25 in 1230 June 17, 1230 June 23, 1230 June
Week 26 in 1230 June 24, 1230 June 30, 1230 June
Week 27 in 1230 July 1, 1230 July 7, 1230 July
Week 28 in 1230 July 8, 1230 July 14, 1230 July
Week 29 in 1230 July 15, 1230 July 21, 1230 July
Week 30 in 1230 July 22, 1230 July 28, 1230 July
Week 31 in 1230 July 29, 1230 August 4, 1230 July / August
Week 32 in 1230 August 5, 1230 August 11, 1230 August
Week 33 in 1230 August 12, 1230 August 18, 1230 August
Week 34 in 1230 August 19, 1230 August 25, 1230 August
Week 35 in 1230 August 26, 1230 September 1, 1230 August / September
Week 36 in 1230 September 2, 1230 September 8, 1230 September
Week 37 in 1230 September 9, 1230 September 15, 1230 September
Week 38 in 1230 September 16, 1230 September 22, 1230 September
Week 39 in 1230 September 23, 1230 September 29, 1230 September
Week 40 in 1230 September 30, 1230 October 6, 1230 September / October
Week 41 in 1230 October 7, 1230 October 13, 1230 October
Week 42 in 1230 October 14, 1230 October 20, 1230 October
Week 43 in 1230 October 21, 1230 October 27, 1230 October
Week 44 in 1230 October 28, 1230 November 3, 1230 October / November
Week 45 in 1230 November 4, 1230 November 10, 1230 November
Week 46 in 1230 November 11, 1230 November 17, 1230 November
Week 47 in 1230 November 18, 1230 November 24, 1230 November
Week 48 in 1230 November 25, 1230 December 1, 1230 November / December
Week 49 in 1230 December 2, 1230 December 8, 1230 December
Week 50 in 1230 December 9, 1230 December 15, 1230 December
Week 51 in 1230 December 16, 1230 December 22, 1230 December
Week 52 in 1230 December 23, 1230 December 29, 1230 December

Calendars 1230

January 1230
MoTuWeThFrSaSu
Week 1123456
Week 278910111213
Week 314151617181920
Week 421222324252627
Week 528293031
February 1230
MoTuWeThFrSaSu
Week 5123
Week 645678910
Week 711121314151617
Week 818192021222324
Week 925262728
March 1230
MoTuWeThFrSaSu
Week 9123
Week 1045678910
Week 1111121314151617
Week 1218192021222324
Week 1325262728293031
April 1230
MoTuWeThFrSaSu
Week 141234567
Week 15891011121314
Week 1615161718192021
Week 1722232425262728
Week 182930
May 1230
MoTuWeThFrSaSu
Week 1812345
Week 196789101112
Week 2013141516171819
Week 2120212223242526
Week 222728293031
June 1230
MoTuWeThFrSaSu
Week 2212
Week 233456789
Week 2410111213141516
Week 2517181920212223
Week 2624252627282930
July 1230
MoTuWeThFrSaSu
Week 271234567
Week 28891011121314
Week 2915161718192021
Week 3022232425262728
Week 31293031
August 1230
MoTuWeThFrSaSu
Week 311234
Week 32567891011
Week 3312131415161718
Week 3419202122232425
Week 35262728293031
September 1230
MoTuWeThFrSaSu
Week 351
Week 362345678
Week 379101112131415
Week 3816171819202122
Week 3923242526272829
Week 4030
October 1230
MoTuWeThFrSaSu
Week 40123456
Week 4178910111213
Week 4214151617181920
Week 4321222324252627
Week 4428293031
November 1230
MoTuWeThFrSaSu
Week 44123
Week 4545678910
Week 4611121314151617
Week 4718192021222324
Week 48252627282930
December 1230
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 1230 starts on December 31, 1229 and ends on January 6, 1230 (ISO 8601, Monday to Sunday). 1230 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 1230 have?

1230 has 52 ISO weeks.

When does week 1 of 1230 start?

Week 1 of 1230 starts on December 31, 1229 and ends on January 6, 1230 (ISO 8601, Monday to Sunday).

When does the last week of 1230 end?

Week 52 of 1230 starts on December 23, 1230 and ends on December 29, 1230 (ISO 8601, Monday to Sunday).

Which years have 53 weeks?

The next years with 53 ISO weeks are 1232, 1237, 1243, 1248, 1254.

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.