Leap Year Calculator
Check whether a year is a leap year and find the next and previous leap years.
Inputs
Formula
- Leap if divisible by 4, except centuries not divisible by 400
The Earth takes about 365.2422 days to orbit the Sun, so we add a day every four years — but skip three of those in every 400 years to stop the calendar drifting. That is why 1900 was not a leap year but 2000 was.
Step-by-step calculation
- 1
Rule
div by 4, not 100, unless 400
Common
Frequently asked questions
What does the Leap Year Calculator do?
Check whether a year is a leap year and find the next and previous leap years. The Leap Year Calculator on OneCalcApp returns the result instantly as you type, together with the formula and the substituted values.
How do I use the Leap Year Calculator?
Enter your values in the input fields, choose the relevant units or options, and the Leap Year Calculator recalculates automatically. You can copy, print or export the result.
Is the Leap Year Calculator free to use?
Yes. The Leap Year Calculator is completely free, needs no sign-up and has no usage limit on OneCalcApp.
How accurate is the Leap Year Calculator?
It uses the standard formula Leap if divisible by 4, except centuries not divisible by 400 and full double-precision arithmetic, so results match a manual calculation to the displayed number of digits.
Does the Leap Year Calculator work on mobile and offline?
Yes. The Leap Year Calculator runs entirely in your browser on phones, tablets and desktops, and your inputs never leave your device.
Where can I find related tools?
OneCalcApp hosts 300+ calculators and converters, including the full Date & Time collection. Related tools are linked at the bottom of every page.
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