Leap Year Checker

Check whether any year is a leap year, see the Gregorian /4 /100 /400 rule, February length, previous and next leap years, and 400-year cycle facts.

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Gregorian Rule Check

Check if a year has February 29

Use the custom year stepper or quick examples to see whether a year is leap, common, century-excluded, or century-approved.

Leap Result

Year statusReadyChoose a year to check the Gregorian leap rule.
February length--
Year length--
Previous leap--
Next leap--
400-year cycle97 leap years
Rule verdict--
No leap-year result yet.
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Overview

Check the Gregorian Leap Year Rule in One Step

A leap year checker answers whether a selected year has 366 days and includes February 29. The tricky part is century years: 1900 was not a leap year, but 2000 was. This tool explains that difference instead of only returning yes or no.

Direct answer: In the Gregorian calendar, a year is a leap year if it is divisible by 4, except years divisible by 100 are not leap years unless they are also divisible by 400. Leap years have 366 days and February has 29 days.

Use this checker for calendar planning, birthday questions, school work, software tests, spreadsheets, project date math, and historical date checks. If you need to measure two dates after checking a year, use the Date Difference Calculator.

Leap Year Checker with custom year input, preset year buttons, Gregorian rule cards, leap year result, February length, and next leap year facts
The Leap Year Checker explains the Gregorian leap-year rule with custom year controls, rule cards, year length, February 29 status, and nearby leap years.
Features

Leap Year Features That Explain the Rule

Custom year stepperUse plus/minus controls or type a year directly without a default-looking browser selector.
Rule cardsSee whether the year passes the divisible by 4, 100, and 400 checks.
Century examplesQuickly compare 1900, 2000, and 2100 to understand century exceptions.
February lengthSee whether February has 28 or 29 days in the selected year.
Nearby leap yearsFind the previous and next leap years around your selected year.
Copyable explanationCopy a concise leap-year explanation for homework, documentation, or spreadsheet notes.
Use Cases

Leap Year Searches Covered on This Page

These examples cover common searches around leap year rules, specific years, and calendar exceptions.

Leap year checkerEnter any year and instantly see whether it is a leap year.
Leap year calculatorThe result explains the calculation using the Gregorian /4 /100 /400 rule.
Is this a leap yearUse the custom year stepper to check the current year, past years, or future years.
Is 2024 a leap yearUse the 2024 preset to see a normal divisible-by-4 leap year.
Is 1900 a leap yearUse the 1900 preset to see why a century year divisible by 100 is not always leap.
Is 2000 a leap yearUse the 2000 preset to see why divisible by 400 overrides the century exception.
Gregorian leap year ruleThe rule cards show the exact checks used by the Gregorian civil calendar.
Next leap year calculatorThe result panel shows the previous and next leap years around the selected year.
Comparison

Why Use a Leap Year Checker Instead of Remembering the Rule?

The rule is short, but century years cause mistakes. The checker shows every step so the answer is easy to trust.

TaskRandomly.onlineManual method
Normal leap yearsShows divisible by 4 and confirms February 29.Mental math is simple but still easy to skip.
Century yearsExplains /100 and /400 exceptions clearly.Many people incorrectly mark 1900 or 2100 as leap years.
Planning calendarsShows year length, February length, and nearby leap years.Manual checking requires extra lookups.
DocumentationCopies the rule explanation for notes or spreadsheets.Requires writing the rule yourself.
Guide

How to Use Leap Year Checker

Enter one year and read the rule cards from left to right.

Choose a year

Use the custom stepper, type a year, or click a preset such as 2024, 1900, 2000, or 2100.

Read the main verdict

The result says whether the selected year is a leap year or common year.

Review the rule cards

Check the divisible by 4, divisible by 100, and divisible by 400 cards to understand why the verdict was reached.

Check February and nearby years

The result panel shows February length, total year days, previous leap year, and next leap year.

Copy the explanation

Use Copy Summary when you need the leap-year result for homework, documentation, spreadsheet comments, or planning notes.

Support

Frequently Asked Questions

How do I know if a year is a leap year?

A year is a leap year if it is divisible by 4, except years divisible by 100 are common years unless they are also divisible by 400.

Is 2024 a leap year?

Yes. 2024 is divisible by 4 and not a century year, so it is a leap year with 366 days and February 29.

Is 1900 a leap year?

No. 1900 is divisible by 100 but not by 400, so it is not a leap year under the Gregorian calendar rule.

Is 2000 a leap year?

Yes. 2000 is divisible by 400, so it is a leap year even though it is also divisible by 100.

Will 2100 be a leap year?

No. 2100 is divisible by 100 but not by 400, so it will be a common year with 365 days.

Why do leap years exist?

Leap years add February 29 to keep the calendar closer to Earths solar year, which is a little longer than 365 days.

How many days are in a leap year?

A leap year has 366 days. February has 29 days instead of 28.

How many leap years are in a 400-year cycle?

The Gregorian calendar has 97 leap years and 303 common years in each 400-year cycle.

What is the difference between Julian and Gregorian leap rules?

The Julian rule uses every fourth year. The Gregorian rule adds century exceptions, which makes years like 1900 common and 2000 leap.

Can I find the next leap year?

Yes. The result panel shows the previous and next leap years around the selected year.

Does leap year affect date calculators?

Yes. Leap years add February 29, which can affect day counts, age calculations, weekday checks, calendar generators, and deadline planning.

Is my year search stored online?

No. The leap-year calculation runs locally in your browser and does not upload your selected year or copied summary.

Still have questions?

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