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Leap Year Checker

A year is leap if divisible by 4, except centuries unless divisible by 400.

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How Leap Year Checker works

A year is leap if divisible by 4, except centuries unless divisible by 400.

Try an example

2000 is leap; 1900 is not.

Good to know

Uses proleptic Gregorian rules, including years before local Gregorian adoption.

Your privacy

Processing happens on this device for this tool. We do not upload your input, put it in share links or save it to your favourites. Closing this tab discards the working input; downloaded results remain wherever you save them.

When this tool is useful

Use Leap Year Checker when you need a quick, local result and want the rule or limitation visible alongside it.

How to use it

  1. Enter the input using the labels shown.
  2. Run the operation and review the result.
  3. Download or copy the result only after checking it.

Checks before you rely on the result

  • Uses proleptic Gregorian rules, including years before local Gregorian adoption.
  • Keep the original input when the operation creates a new copy.
  • Use the related tools below when the next step needs a different format.

This page is maintained with the tool implementation and its deterministic tests. If the result looks wrong, report the issue with a non-sensitive example.

Read the Leap Year Checker instructions

A useful next step

Date Difference
Add / Subtract Days
Business Days Calculator
Made for clarity. Built to be useful.Report an issue