Leap Year Checker
Check whether a given year is a leap year, instantly in your browser.
How to use the Leap Year Checker
- Enter a year, for example 2028.
- Click Run to see whether it is a leap year and which rule applies.
- Check century years such as 1900, 2000 and 2100 to see the 100 and 400 exceptions in action.
How the Leap Year Checker works
The Gregorian calendar adds an extra day, 29 February, to keep the calendar in step with the Earth's orbit of about 365.2422 days. The rule is:
A year divisible by 4 is a leap year, except a year divisible by 100, which is not, unless it is also divisible by 400.
So 2024 and 2028 are leap years, 1900 and 2100 are not, and 2000 was. This keeps the average calendar year at 365.2425 days.
Frequently asked questions
- Is this tool free?
- Yes. Check leap years at no cost, with no account required.
- What is the leap year rule?
- A year is a leap year if it is divisible by 4, except for century years, which must also be divisible by 400.
- Why is the year 2000 a leap year but 1900 wasn't?
- 2000 is divisible by 400, while 1900 is divisible by 100 but not by 400, so it was skipped under the leap year rule.