Week 17 of 2026 runs April 20 to April 26

ISO week 17 of 2026 begins on Monday, April 20, 2026 and ends on Sunday, April 26, 2026. It has already passed; the current week is 39. The week covers April only.

What dates are in week 17?

Week 17 of 2026 contains Earth Day on April 22. 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 17 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 17 is the 17th Monday-to-Sunday block of 2026, which lands on April 20. All seven dates sit inside 2026, so the ISO year and the calendar year agree for this week.

When is week 17 in other years?

Week 17 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 April 20 in 2026 to April 26 in 2027.

How far away is week 17?

Today is Wednesday, September 23, 2026, which sits in ISO week 39 of 2026. Week 17 of 2026 closed 150 days ago. The same week number in the following year is listed in the table above.

Questions

What dates are in week 17 of 2026?

Monday April 20, 2026 through Sunday April 26, 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

Jump to a week

All 53 weeks · Weeks in 2026 · Day of the year · Weeks until any date · Date calculator