Days Since Date

Week 3 of 2026 runs January 12 to January 18

ISO week 3 of 2026 begins on Monday, January 12, 2026 and ends on Sunday, January 18, 2026. It has already passed; the current week is 39. The week covers January only.

Week 3 starts
January 12
Monday, 2026
Week 3 ends
January 18
Sunday, 2026
Weeks in 2026
53
week 3 of 53
Days 12 to 18 of 2026 · ISO 8601 weeks run Monday to Sunday

What dates are in week 3?

WeekdayDateDay of yearNotes
MondayJanuary 12, 202612
TuesdayJanuary 13, 202613
WednesdayJanuary 14, 202614
ThursdayJanuary 15, 202615
FridayJanuary 16, 202616
SaturdayJanuary 17, 202617
SundayJanuary 18, 202618

No holiday or widely marked observance falls inside week 3 of 2026. The seven dates always run Monday through Sunday, which is the part of ISO 8601 that most often catches people out: a week that starts on Sunday is a different convention and gives a different number.

How ISO week 3 is worked out

ISO 8601 fixes week one as the week containing the first Thursday of January, which is the same as saying the week containing 4 January, or the week holding the majority of its days in the new year. Counting forward from there, week 3 is the 3rd Monday-to-Sunday block of 2026, which lands on January 12. All seven dates sit inside 2026, so the ISO year and the calendar year agree for this week.

Week number
3
Starts
January 12
Ends
January 18
Weeks left
50
Quarter
Q1

When is week 3 in other years?

YearMondaySundayWeeks in year
2026January 12January 1853
2027January 18January 2452
2028January 17January 2352
2029January 15January 2152
2030January 14January 2052

Week 3 shifts by a day or two each year because a year is 52 weeks plus one or two days, so the Monday that opens it moves from January 12 in 2026 to January 18 in 2027.

How far away is week 3?

Today is Wednesday, September 23, 2026, which sits in ISO week 39 of 2026. Week 3 of 2026 closed 248 days ago. The same week number in the following year is listed in the table above.

Questions

What dates are in week 3 of 2026?
Monday January 12, 2026 through Sunday January 18, 2026.
What week is it now?
ISO week 39 of 2026. Today is Wednesday, September 23, 2026.
How many weeks does 2026 have?
53. The 2026 week count page explains the rule.
Do ISO weeks start on Monday or Sunday?
Monday. A Sunday-first week is a different convention and can give a different week number for the same date.

Nearby weeks

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