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Check whether a year is a leap year, see why, and list the leap years before and after it.
Also covers: Is it a leap year · Leap year list
Gregorian calendar rule: divisible by 4, except century years not divisible by 400.
Leap year?
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The current year by default. You'll see whether it's a leap year, the rule that decides it, the previous and next leap years, and all leap years within 20 years.
A year is a leap year if it's divisible by 4, except century years, which must also be divisible by 400. So 2024 is a leap year, 1900 isn't, and 2000 is.
A solar year is about 365.2422 days. Adding a day every 4 years overcorrects slightly, so the Gregorian calendar skips three leap days every 400 years, keeping the calendar within about a day of the seasons for thousands of years.
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