Days in Month Calculator

Find how many days are in any month and year — accounting for leap-year rules for February.

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March 2026

31

days in March 2026

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Days in a month calculator: how many days in any month and year

The days-in-month calculator tells you exactly how many days are in any month of any year — accounting for February's varying length in leap years. Enter a month and year to get the day count instantly, along with the first and last day of the month and how many weekdays and weekend days it contains.

How the day count is determined

Eleven months have fixed day counts: January (31), March (31), April (30), May (31), June (30), July (31), August (31), September (30), October (31), November (30), December (31). February is the exception: it has 28 days in a common year and 29 days in a leap year. The leap year rule is: divisible by 4, except century years not divisible by 400.

A handy mnemonic for the fixed months is the knuckle rule: make a fist and count knuckles and valleys starting from the index-finger knuckle. Knuckles are 31-day months (January, March, May, July, August, October, December) and valleys are 30-day months or February.

February days = 29 if leap year, else 28

All other months are fixed: Jan/Mar/May/Jul/Aug/Oct/Dec = 31; Apr/Jun/Sep/Nov = 30.

Weekdays in month = Total days − Saturdays − Sundays

Varies by month and by which day of the week the month starts.

Why this matters for planning and finance

Billing and payroll cycles that run on a monthly basis must account for variable month lengths. A monthly salary divided by the number of days in the month gives the daily rate for prorated calculations. February is frequently the source of proration errors because many people assume it always has 28 days.

Project managers scheduling deliveries at the end of each month — known as end-of-month or EOM scheduling — need to know the exact last day of each month. Adding one month to 31 January should land on 28 or 29 February (not 31 February, which does not exist). The days-in-month calculator prevents these off-by-one scheduling errors.

Frequently asked questions

How many days does February have in 2024?

2024 is a leap year (divisible by 4 and not a century year), so February 2024 has 29 days. The next time February has 29 days is 2028.

 Which months have 30 days?

April, June, September, and November each have 30 days every year. All other months (except February) have 31 days. February has 28 days in common years and 29 days in leap years.

 How many weekdays are in a month?

A month with 31 days contains either 21 or 23 weekdays, depending on which day of the week the month starts. Most months contain 21 or 22 weekdays. February can have as few as 20 weekdays. The calculator shows the exact weekday count for any month and year.

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More from nearby categories

These related calculators come from the same leaf category, nearby sibling categories, or the same top-level topic.

Days in Year Calculator

Find the exact number of days in any year — 365 for common years or 366 for leap years — with a clear leap-year note.

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Weekdays in Year Calculator

Count how many times each day of the week appears in a selected year, with totals for weekdays and weekend days.

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Day of Week Calculator

Find the day of the week for any historical or future date, plus its day of year, ISO week number, and weekend status.

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Leap Year Calculator

Check whether a given year is a leap year, see the days it contains, and find the nearest past and upcoming leap years.

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