Leap Year Calculator
Is a year a leap year? Days in the year, February length and the next leap year.
Quick answer
- Formula: Leap if (year ÷ 4 remainder 0 AND year ÷ 100 remainder ≠ 0) OR year ÷ 400 remainder 0
- Worked example — Is it a leap year?: Yes (full example below).
Leap Year Calculator
| Is it a leap year? | Yes |
| Days in the year | 366 |
| Days in February | 29 |
| Next leap year | 2028 |
2024 is a leap year: 366 days, 29 days in February, and the next leap year after it is 2028.
Check any year against the Gregorian leap-year rule: leap years have 366 days with a February 29, and they keep the calendar aligned with Earth's orbit.
Along with the yes/no answer you get the number of days in the year, the length of its February, and the next leap year after the one entered.
The formula
Worked example
2024 is a leap year: 366 days, 29 days in February, and the next leap year after it is 2028.
The example is pre-loaded in the result panel — press Calculate with your own numbers to replace it.
Frequently asked questions
Why is 1900 not a leap year but 2000 is?
Century years must be divisible by 400. 1900 is divisible by 100 but not 400, so it was a common year; 2000 is divisible by 400, so it was a leap year.
Why do leap years exist?
A solar year is about 365.2422 days. Adding February 29 roughly every four years — with the century corrections — keeps calendar dates aligned with the seasons.
Category: Date & Time calculators
Sources & methodology
This calculator applies the formula shown on this page exactly as written, using the standard definitions for its inputs. Results are computed from the values you enter — no data is stored — and are rounded only for display.
Content last reviewed by CalcHub Editorial.
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