Leap Year Calculator
Check whether any year is a leap year, see the reasoning behind the answer, and browse nearby leap years.
2026 is not a leap year
2026 is not divisible by 4, so it is not a leap year.
Previous leap years
Upcoming leap years
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Pro Tips
- •The rule is: divisible by 4, except century years, which must be divisible by 400 - this is why 2000 was a leap year but 1900 was not
- •Leap years exist to keep the calendar synchronized with Earth's orbit, which takes about 365.2425 days, not exactly 365
- •Leap years occur in most, but not all, multiples of 4, so always check century years carefully
- •This works for any year, including years far in the past or future, using the standard Gregorian calendar rule
Most Popular
Most users check the current year or a birth year, and February 29 babies often check whether their birth year and other years are leap years
When to Use This Tool
Double-check that a date library or custom calendar function handles leap years correctly.
Teach the leap year rule, including the century year exception, with real examples.
Check whether a specific year includes a February 29 for scheduling purposes.
Verify whether a historical year was a leap year while researching records.
How It Works
Check whether the year is evenly divisible by 4
If it's also divisible by 100, require it to also be divisible by 400 to still count as a leap year
Apply the standard Gregorian calendar rule to determine the final answer
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Frequently Asked Questions
What is the leap year rule?
A year is a leap year if it's divisible by 4, except for century years (divisible by 100), which must also be divisible by 400. This is why 2000 was a leap year but 1900 and 2100 are not.
Why do we need leap years at all?
Earth takes about 365.2425 days to orbit the sun, not exactly 365. Adding an extra day roughly every 4 years keeps our calendar aligned with the seasons over long periods.
Does this work for years before 1582?
This calculator applies the modern Gregorian calendar rule. Many countries didn't adopt the Gregorian calendar until 1582 or later, so applying this rule to earlier dates is a simplification, not historically precise.
Is my data sent to a server?
No. The calculation happens entirely in your browser.
How often do leap years occur?
On average, a leap year occurs once every 4 years, though century years not divisible by 400 break that pattern roughly 3 times every 400 years.