Leap Year Checker

Check whether any year is a leap year and see exactly why, with the nearby leap years listed.

Leap year checker

Year

Result: —

Why: —

Rule checks: —

Days in the year: — · February has —

Previous leap years: —

Next leap years: —

The Gregorian rule: a year is a leap year if it is divisible by 4, except for century years, which must be divisible by 400.

Common questions about the free online leap year checker.

A year is a leap year if it is divisible by 4. Century years are the exception and must also be divisible by 400, so 1900 was not a leap year but.

A solar year is about 365.2422 days long. Adding an extra day almost every four years keeps the calendar aligned with the seasons.

Divide the year by 4, by 100 and by 400. It is a leap year when it divides by 4 and either does not divide by 100 or does divide by 400.

No. It is divisible by 4 and by 100 but not by 400, so it was a common year of 365 days.

Yes. It is divisible by 400, which makes it a leap year, and it was the last leap year of the twentieth century.

Yes. It is divisible by 4 and is not a century year, so 2024 had 366 days and February had 29 days.

After 2024 the next leap years are 2028, 2032 and 2036. The tool lists the next five years for whichever year you enter.

No. The Julian calendar adds a leap day every four years without the century exception, and the Hebrew and Islamic calendars use entirely different.

No. The check runs entirely in your browser and nothing is sent anywhere.

Last updated: October 10, 2026