Week numbers 2027

Calendar 2027

2027 has 52 ISO weeks. Week 1 begins on January 4 and week 52 ends on January 2. The calendar above is set to print these numbers down the margin.

How ISO week numbering works

Week 1 of a year is the week containing its first Thursday — equivalently, the week containing 4 January. Weeks always run Monday to Sunday. Because of that rule, the first days of January can belong to the last week of the previous year, and the last days of December can already be week 1 of the next.

2027 has the usual 52 weeks. Years get a 53rd when they start on a Thursday, or on a Wednesday in a leap year.

Every week of 2027

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

Print a calendar with these numbers

Week numbers are a switch on every layout, not a separate product — see calendar with week numbers for where they appear in each one. They stay Monday-based even if you set the calendar itself to start on Sunday, so the numbers keep matching everybody else's.

Months of 2027

Other years