---
title: "Leap Year Calculator | Numequo"
description: "Check whether a Gregorian calendar year contains 365 or 366 days. Get a clear result with the formula, examples and useful explanations."
canonical: "https://www.numequo.com/time/dates-calendar/leap-year-calculator/"
locale: "en"
---
[Numequo](https://www.numequo.com/) › [Time](https://www.numequo.com/time/) › [Dates and calendar](https://www.numequo.com/time/dates-calendar/)

# Leap Year Calculator

Enter a year to test the Gregorian leap-year rules.

## Input data

- **Year** - type: number; default: 2028; min: 1; max: 9999; step: 1

## How it works

A year is leap when divisible by 4, except century years unless they are also divisible by 400.

## Quick examples

- **2028** - Year: 2028
- **2100** - Year: 2100
- **2000** - Year: 2000

## Understanding your result

A leap year has 29 days in February and 366 days in total.

Last verified: 29 September 2026 (2026-09-29)

## Frequently asked questions

### Why is 2100 not a leap year?

It is divisible by 100 but not by 400.

### Why was 2000 a leap year?

Century years remain leap years when divisible by 400.

### How many days are in a leap year?

366 days.

## Related calculators

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- [Day of the Week Calculator](https://www.numequo.com/time/dates-calendar/day-of-week-calculator/) - Find which weekday corresponds to any valid calendar date.
- [Date Difference Calculator](https://www.numequo.com/time/dates-calendar/date-difference-calculator/) - Count days and weeks between any two dates.
- [Age Calculator](https://www.numequo.com/time/dates-calendar/age-calculator/) - Calculate an exact age between two dates.
- [Date Add or Subtract Calculator](https://www.numequo.com/time/dates-calendar/date-add-subtract-calculator/) - Add or subtract days, weeks, months or years from any calendar date.
- [Business Days Calculator](https://www.numequo.com/time/dates-calendar/business-days-calculator/) - Count business days between two dates with configurable weekends and holidays.

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