Week numbers 391

391 has 52 ISO weeks. Week 1: Dec 31, 390 – Jan 6, 391 · Week 52: Dec 23 – 29

391 at a glance

Weeks in 39152
Week 1December 31, 390 – January 6, 391
Week 52December 23, 391 – December 29, 391
Days in 391365
Leap yearNo

All Weeks in 391

Week From To Month
Week 1 in 391 December 31, 390 January 6, 391 December / January
Week 2 in 391 January 7, 391 January 13, 391 January
Week 3 in 391 January 14, 391 January 20, 391 January
Week 4 in 391 January 21, 391 January 27, 391 January
Week 5 in 391 January 28, 391 February 3, 391 January / February
Week 6 in 391 February 4, 391 February 10, 391 February
Week 7 in 391 February 11, 391 February 17, 391 February
Week 8 in 391 February 18, 391 February 24, 391 February
Week 9 in 391 February 25, 391 March 3, 391 February / March
Week 10 in 391 March 4, 391 March 10, 391 March
Week 11 in 391 March 11, 391 March 17, 391 March
Week 12 in 391 March 18, 391 March 24, 391 March
Week 13 in 391 March 25, 391 March 31, 391 March
Week 14 in 391 April 1, 391 April 7, 391 April
Week 15 in 391 April 8, 391 April 14, 391 April
Week 16 in 391 April 15, 391 April 21, 391 April
Week 17 in 391 April 22, 391 April 28, 391 April
Week 18 in 391 April 29, 391 May 5, 391 April / May
Week 19 in 391 May 6, 391 May 12, 391 May
Week 20 in 391 May 13, 391 May 19, 391 May
Week 21 in 391 May 20, 391 May 26, 391 May
Week 22 in 391 May 27, 391 June 2, 391 May / June
Week 23 in 391 June 3, 391 June 9, 391 June
Week 24 in 391 June 10, 391 June 16, 391 June
Week 25 in 391 June 17, 391 June 23, 391 June
Week 26 in 391 June 24, 391 June 30, 391 June
Week 27 in 391 July 1, 391 July 7, 391 July
Week 28 in 391 July 8, 391 July 14, 391 July
Week 29 in 391 July 15, 391 July 21, 391 July
Week 30 in 391 July 22, 391 July 28, 391 July
Week 31 in 391 July 29, 391 August 4, 391 July / August
Week 32 in 391 August 5, 391 August 11, 391 August
Week 33 in 391 August 12, 391 August 18, 391 August
Week 34 in 391 August 19, 391 August 25, 391 August
Week 35 in 391 August 26, 391 September 1, 391 August / September
Week 36 in 391 September 2, 391 September 8, 391 September
Week 37 in 391 September 9, 391 September 15, 391 September
Week 38 in 391 September 16, 391 September 22, 391 September
Week 39 in 391 September 23, 391 September 29, 391 September
Week 40 in 391 September 30, 391 October 6, 391 September / October
Week 41 in 391 October 7, 391 October 13, 391 October
Week 42 in 391 October 14, 391 October 20, 391 October
Week 43 in 391 October 21, 391 October 27, 391 October
Week 44 in 391 October 28, 391 November 3, 391 October / November
Week 45 in 391 November 4, 391 November 10, 391 November
Week 46 in 391 November 11, 391 November 17, 391 November
Week 47 in 391 November 18, 391 November 24, 391 November
Week 48 in 391 November 25, 391 December 1, 391 November / December
Week 49 in 391 December 2, 391 December 8, 391 December
Week 50 in 391 December 9, 391 December 15, 391 December
Week 51 in 391 December 16, 391 December 22, 391 December
Week 52 in 391 December 23, 391 December 29, 391 December

Calendars 391

January 391
MoTuWeThFrSaSu
Week 1123456
Week 278910111213
Week 314151617181920
Week 421222324252627
Week 528293031
February 391
MoTuWeThFrSaSu
Week 5123
Week 645678910
Week 711121314151617
Week 818192021222324
Week 925262728
March 391
MoTuWeThFrSaSu
Week 9123
Week 1045678910
Week 1111121314151617
Week 1218192021222324
Week 1325262728293031
April 391
MoTuWeThFrSaSu
Week 141234567
Week 15891011121314
Week 1615161718192021
Week 1722232425262728
Week 182930
May 391
MoTuWeThFrSaSu
Week 1812345
Week 196789101112
Week 2013141516171819
Week 2120212223242526
Week 222728293031
June 391
MoTuWeThFrSaSu
Week 2212
Week 233456789
Week 2410111213141516
Week 2517181920212223
Week 2624252627282930
July 391
MoTuWeThFrSaSu
Week 271234567
Week 28891011121314
Week 2915161718192021
Week 3022232425262728
Week 31293031
August 391
MoTuWeThFrSaSu
Week 311234
Week 32567891011
Week 3312131415161718
Week 3419202122232425
Week 35262728293031
September 391
MoTuWeThFrSaSu
Week 351
Week 362345678
Week 379101112131415
Week 3816171819202122
Week 3923242526272829
Week 4030
October 391
MoTuWeThFrSaSu
Week 40123456
Week 4178910111213
Week 4214151617181920
Week 4321222324252627
Week 4428293031
November 391
MoTuWeThFrSaSu
Week 44123
Week 4545678910
Week 4611121314151617
Week 4718192021222324
Week 48252627282930
December 391
MoTuWeThFrSaSu
Week 21
Week 492345678
Week 509101112131415
Week 5116171819202122
Week 5223242526272829
Week 13031

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 391 starts on December 31, 390 and ends on January 6, 391 (ISO 8601, Monday to Sunday). 391 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 391 have?

391 has 52 ISO weeks.

When does week 1 of 391 start?

Week 1 of 391 starts on December 31, 390 and ends on January 6, 391 (ISO 8601, Monday to Sunday).

When does the last week of 391 end?

Week 52 of 391 starts on December 23, 391 and ends on December 29, 391 (ISO 8601, Monday to Sunday).

Which years have 53 weeks?

The next years with 53 ISO weeks are 392, 398, 404, 409, 415.

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.