Leap Year Calculators

Enter a year to test the leap-year rules, or a start and end up to 2000 years apart to list every leap year in that span.

Enter a start and end year from 1600 to 4000. See every leap year in that span, or check one year, on a timeline.

Find the next leap year from any given year with visual timeline, leap year checker, and educational content about the Gregorian calendar 400-year cycle.

Enter a year to see if it is a leap year, when the previous and next leap years fall, and how the leap-year rule works.