What makes a year a leap year?

A year is a leap year if: (1) it's divisible by 4, AND (2) if it's divisible by 100, it must also be divisible by 400. For example, 2024 is a leap year (divisible by 4), 1900 was not (divisible by 100 but not 400), but 2000 was (divisible by 400).

Why do we have leap years?

A solar year is about 365.25 days, not exactly 365. Without leap years, our calendar would drift and seasons would shift over centuries. Adding a day every 4 years (with century exceptions) keeps the calendar aligned with Earth's orbit.

How often do leap years occur?

Leap years occur every 4 years, except for years divisible by 100 (which are skipped), unless they're also divisible by 400 (which are kept). This means there are 97 leap years every 400 years, not 100.

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Date & TimeVerifiedFeb 2026

Leap Year Calculator

Name: Leap Year Calculator
Author: Biggest Calculator Hub

Determine if any year is a leap year using the Gregorian calendar rules. See the next and previous leap years and understand why leap years exist.

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How to Use the Leap Year Calculator

This free leap year calculator helps you quickly calculate is leap year. Simply enter your values in the fields above and click "Calculate" to see your results instantly.

Understanding Your Results

After entering your information, the calculator will display your results including is leap year, days in year, next leap year, previous leap year, explanation. Each result is calculated using standard formulas used by financial professionals and experts in the field.

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