Dates & Time

Excel formula for Number of days in a month

Find how many days are in the month a date belongs to.

Copy this formula

=DAY(EOMONTH(A2, 0))

How the formula works

EOMONTH(A2, 0) returns the last day of the month, and DAY pulls out its day number — which is exactly the count of days that month. It handles February and leap years automatically.

Examples

=DAY(EOMONTH(DATE(2026,2,1), 0))→28

February 2026 has 28 days.

FAQ

How do I check for a leap year?

=DAY(DATE(YEAR(A2),3,0))=29 returns TRUE for a leap year.

Related formulas

First or last day of the month Days between two dates

Functions used

DAY EOMONTH

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