ISO week 2027-W04

Week 4, 2027

Monday, January 25 – Sunday, January 31, 2027

ISO week 4 of 2027 (2027-W04) runs from Monday, January 25, 2027 to Sunday, January 31, 2027.

This week starts 15 weeks from now. The current week is week 42, 2026.

The 7 days of week 4

Dates in week 4, 2027
Day	Date	Day of year	US week	ISO date
Monday	January 25, 2027	25 of 365	5	2027-W04-1
Tuesday	January 26, 2027	26 of 365	5	2027-W04-2
Wednesday	January 27, 2027	27 of 365	5	2027-W04-3
Thursday	January 28, 2027	28 of 365	5	2027-W04-4
Friday	January 29, 2027	29 of 365	5	2027-W04-5
Saturday	January 30, 2027	30 of 365	5	2027-W04-6
Sunday	January 31, 2027	31 of 365	6	2027-W04-7

Week 4 at a glance

ISO code: 2027-W04 (Monday is 2027-W04-1, Sunday is 2027-W04-7)
Month: January
Quarter: Q1 of 2027
Day of year: Days 25–31 of 365
US week number: Monday–Saturday: US week 5; Sunday: US week 6 (Sunday-start weeks, week 1 contains January 1)
Even or odd: Week 4 is an even week
Weeks left: After this week, 48 ISO weeks remain in 2027 (52 weeks in total)
Year progress: By Sunday, 8% of 2027 has passed

Holidays and key dates

There are no US federal holidays, daylight saving time changes or quarter starts in week 4 of 2027.

Week numbers follow ISO 8601: weeks start on Monday and week 1 contains the first Thursday of the year. US weeks start on Sunday, with week 1 containing January 1.

Questions about week 4, 2027

What are the dates of week 4 in 2027?

Week 4 of 2027 starts on Monday, January 25, 2027 and ends on Sunday, January 31, 2027.

What month is week 4 of 2027?

Week 4 falls in January. By the Thursday rule that ISO 8601 uses for years and quarters, it counts as a January week.

How do I get week 4 of 2027 in Excel or Google Sheets?

=ISOWEEKNUM(DATE(2027,1,25)) returns 4. To go the other way, =DATE(2027,1,4)-WEEKDAY(DATE(2027,1,4),2)+1+(4-1)*7 returns the Monday, January 25, 2027.