Leap Year Checker
Enter any year to check whether it is a leap year under the exact Gregorian rules, and list all leap years between any two years.
Enter a year to check it.
How to use
- Type a year in the box to check instantly whether it is a leap year and why.
- Change the year in the box to see the result update live, with the exact rule that applies shown.
- Set a start and end year to list every leap year in that range at once.
- Read the result line: leap years are divisible by 4, except centuries, which must divide by 400.
Tips
- Centuries are the trick: 1900 and 2100 are not leap years, but 2000 was, because only centuries divisible by 400 qualify.
- February gains the extra day, so schedules and contracts tied to February dates deserve a second look in leap years.
- The range list is handy for planning recurring dates, birthdays and anniversaries years ahead.
Gregorian rule: a year is a leap year if it is divisible by 4, except century years, which must be divisible by 400. So 2000 was a leap year but 1900 and 2100 are not.