Mondo Knows Facts
Century years are only leap years if divisible by four hundred
The Gregorian calendar skips leap days on most century years to fix solar drift
The Gregorian calendar adds an extra day every four years, except for years ending in double zeroes unless divisible by 400. This rule means 1900 was not a leap year, but 2000 was. The adjustment corrects the small fraction of a day gained by basic four-year leap cycles over solar years.
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Tags: calendar, time, astronomy
Century years are only leap years if divisible by four hundred: the short answers
- Where does this come from, and can I check it?
- The Gregorian calendar skips leap days on most century years to fix solar drift. The figure is taken from Time and Date, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.
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