Complete List of Leap Years (1900–2100)

A year is a leap year if it meets the following conditions:

1. Divisible by 4 → leap year (e.g. 1904, 2004)
2. Exception: Century years (1800, 1900, 2100) are not leap years — even though they are divisible by 4.
3. Exception to the exception: Century years divisible by 400 are leap years (e.g. 2000).

In practice: 1900 is NOT a leap year (divisible by 100 but not 400). 2000 IS a leap year (divisible by 400). 2100 will NOT be a leap year.

Note: 1900 and 2100 are not leap years. The next leap year after 2096 is 2104.

Earth takes approximately 365.25 days to complete one orbit around the sun. A standard calendar year has only 365 days, which means we lose about a quarter of a day each year. Without leap years, the calendar would drift roughly 1 day every 4 years — and after a century, the seasons would be off by 25 days.

The leap year system (established by the Gregorian calendar in 1582) corrects for this drift by adding an extra day — February 29 — in most years divisible by 4.