Leap Year Calculator
Determine whether any year is a leap year and discover why — with clear explanations of the rules.
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365 Days
February has 28 days
2026 is not divisible by 4 — it is not a leap year.
365
2028
Next leap year
2024
Last leap year
2026 is not a century year.
How the Leap Year Rule Works
- Divisible by 4: Most years divisible by 4 are leap years.
- Divisible by 100: Century years are NOT leap years unless...
- Divisible by 400: ...they are also divisible by 400.
Smart Insights
How It Works
The leap year rules were established by Pope Gregory XIII in 1582. They correct for the fact that Earth orbit around the sun takes approximately 365.2422 days — slightly more than 365 days.
Frequently Asked Questions
What is a leap year?
A leap year has 366 days instead of 365. An extra day (February 29) is added to keep our calendar aligned with the Earth orbit.
How do I know if a year is a leap year?
A year is a leap year if it is divisible by 4, except for century years (years divisible by 100), which are only leap years if also divisible by 400.
Why do we have leap years?
Earth orbit takes approximately 365.2422 days. Without leap years, our calendar would drift by about 24 days every century.
What happens on February 29 in a non-leap year?
February has 28 days in common years. February 29 only exists in leap years.
Why was the year 2000 a leap year?
2000 is divisible by 400, so it is a leap year despite being a century year.
Why is 2100 not a leap year?
2100 is divisible by 100 but not by 400, so it is a common year despite being divisible by 4.
Last reviewed: July 20, 2026