Leap Year Checker

The Leap Year Checker tells you whether a given year has 366 days, and explains why in plain language.

Enter any year and it reports a clear yes or no, the reasoning behind it, and the next leap year that follows.

The rule is deceptively tricky.

A year is a leap year if it is divisible by four — but century years are the exception, and are only leap years if they are also divisible by four hundred.

That is why 2000 was a leap year while 1900 and 2100 are not.

People routinely forget the century rule, which is exactly where date arithmetic goes wrong.

This tool applies the full Gregorian rule and spells out which branch your year falls into, so you are not just told the answer but shown the why.

Knowing the leap status of a year matters for anything that touches 29 February: birthdays and anniversaries on that date, billing cycles, payroll, and any calculation that assumes a fixed year length.

The next-leap-year figure is handy when you are scheduling something that should land on a 29 February.

The whole thing is instant, runs in your browser, and never leaves your device.