Why do leap years occur?

Leap years exist to keep our calendar aligned with Earth's orbit around the Sun. Since Earth takes about 365.25 days to complete one orbit, we add an extra day every 4 years to account for the accumulated quarter-day difference. However, the rule has exceptions: years divisible by 100 are not leap years unless they're also divisible by 400. This is why 2000 was a leap year, but 1900 was not. This complex system ensures our calendar stays accurate over centuries.

Leap Year Checker - Is It a Leap Year?

Calculators / Date Calculators / Leap Year Checker

Check Leap Year

Enter any year to check if it's a leap year. A leap year has 366 days instead of 365, with an extra day added to February (29th). See the dynamic table below for leap years from the past decade to the next decade.

Leap Years: Past 10 Years & Next 10 Years

Year	Leap Year	Days

Frequently Asked Questions

A leap year is a year that contains an extra day, February 29th, making it 366 days instead of the usual 365. Leap years occur every 4 years to help synchronize the calendar year with the solar year, which is approximately 365.25 days long. The extra day compensates for the roughly 6 hours difference between the calendar year and the actual time it takes Earth to orbit the Sun.

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