Leap Year Checker Calculator
Enter a year to check whether it is a leap year.
Leap Year Checker Calculator
Check whether a given year is a leap year using the standard Gregorian calendar rule.
A leap year adds an extra day (February 29) to keep the calendar aligned with Earth’s orbit. The Gregorian calendar rule is: a year is a leap year if divisible by 4, unless it is also divisible by 100 — unless it is also divisible by 400, in which case it is a leap year after all.
Example
- With the default values shown above, this calculator returns: Divisible by 4 ≈ 0; Divisible by 100 ≈ 0; Divisible by 400 ≈ 0; Leap Year Code ≈ 0; Result: Not a leap year.
Frequently Asked Questions
What is the leap year rule?
A year is a leap year if it is divisible by 4, except century years (divisible by 100), which are only leap years if also divisible by 400 — so 2000 was a leap year, but 1900 was not.
Why do we have leap years?
Earth’s orbit around the sun takes about 365.24 days, not exactly 365 — adding a leap day roughly every four years keeps the calendar synchronized with the seasons over time.