The leap year calculator determines whether a given year is a leap year (366 days with February 29th) or a common year (365 days). Leap years occur roughly every four years to keep our calendar aligned with Earth's orbit.
The rule: a year is a leap year if it's divisible by 4, except for years divisible by 100 (unless also divisible by 400). So 2000 was a leap year, but 1900 was not.
This is useful for birthday planning (if you're born on February 29th), calendar creation, date validation, historical research, or understanding why some years have an extra day.
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Frequently Asked Questions
To keep the calendar synchronized with Earth's orbit, which takes about 365.25 days.
Divisible by 4, except century years unless divisible by 400.
Yes, because it's divisible by 400.
No, it's divisible by 100 but not by 400.
2028 is the next leap year after 2024.