Time & dates
Leap year calculator
Enter a year to see whether it is a leap year, how many days February has, and the previous, next and upcoming leap years.
A year divisible by 100 is a leap year only if it is also divisible by 400, so 1900 was not but 2000 was.
The leap year rule
A leap year adds a 29th day to February to keep the calendar in step with the Earth's orbit. The test has three parts: a year is a leap year if it is divisible by 4, except that years divisible by 100 are not, unless they are also divisible by 400. So 2024 is a leap year (divisible by 4), 1900 was not (divisible by 100 but not 400), and 2000 was (divisible by 400). Checking 2026: it is not divisible by 4, so it is a common year with 28 days in February, and the nearest leap years are 2024 before it and 2028 after.
The reason for the fiddly exception is astronomy. A full orbit takes about 365.2422 days, not a tidy 365.25, so adding a day every four years slightly overshoots. Dropping three leap days every 400 years, by skipping the century years that are not divisible by 400, corrects almost all of the drift, leaving an error of about one day in 3,200 years.
| Leap year | 29 February falls on |
|---|---|
| 2028 | Tuesday |
| 2032 | Sunday |
| 2036 | Friday |
| 2040 | Wednesday |
| 2044 | Monday |
| 2048 | Saturday |
Why it matters
The leap day keeps the seasons anchored: without it the calendar would slip about a day every four years, and after a few centuries the solstices would land in the wrong months. For everyday use the main effects are smaller. A leap year has 366 days and 53 Saturdays or Sundays in some years, payroll with 27 fortnightly pay periods crops up occasionally, and anyone born on 29 February gets a true birthday only once every four years. Software has historically mishandled the rule around century years, so 2000 being a leap year quietly avoided a round of date bugs. The upcoming leap years are listed above with the weekday each 29 February lands on.
Frequently asked questions
Is 2026 a leap year?
No. 2026 is not divisible by 4, so February 2026 has 28 days. The closest leap years are 2024 and 2028.
Why are some century years not leap years?
Years divisible by 100 skip the leap day unless they are also divisible by 400. This removes three extra days every 400 years to match the orbit, so 1700, 1800 and 1900 were common years while 2000 was a leap year.
How often does a leap year happen?
Almost every four years. The exception is century years not divisible by 400, so across a 400-year span there are 97 leap years rather than 100.