Leap Year Checker

Instantly check whether any year is a leap year, see why, and browse the upcoming leap years. Free and private — the check runs entirely in your browser.

How to use the leap year checker

  1. Enter a year. Type any year from 1 to 99999 — the current year is filled in for you as a starting point.
  2. Read the verdict. The tool instantly tells you whether the year is a leap year, explains which divisibility rule applies, and shows how many days the year and its February have.
  3. Browse nearby leap years. See the previous and next leap year and a list of the ten upcoming leap years, ready to copy for planning birthdays, contracts or software tests.

About this tool

A leap year adds a 366th day — February 29 — to keep the calendar aligned with the Earth's orbit, which takes about 365.2425 days. The Gregorian rule is: a year is a leap year if it is divisible by 4, except century years (divisible by 100), which must also be divisible by 400. That's why 2024 and 2000 are leap years but 1900 and 2100 are not. This free leap year checker applies the full rule for you and lists the leap years ahead, which is handy for February 29 birthdays, payroll and interest calculations, and testing date-handling code.

The check is pure arithmetic performed locally in your browser — nothing is sent to any server. Want to know which weekday a particular date falls on? Try the companion Day of the Week tool.

Frequently asked questions

When is the next leap year?

The next leap year after 2026 is 2028. Leap years normally arrive every four years (2028, 2032, 2036 …), with the rare exception of century years like 2100, which skip the leap day because they are not divisible by 400.

Why are 1900 and 2100 not leap years?

The solar year is slightly shorter than 365.25 days, so adding a leap day every 4 years without exception would drift the calendar. The Gregorian calendar therefore drops the leap day in century years unless they are divisible by 400 — keeping the average year at 365.2425 days.

Does the checker work for years before 1582?

Yes, but note that the Gregorian calendar was only introduced in 1582. For earlier years the tool applies the modern (proleptic Gregorian) rule; historically, the Julian calendar in use back then treated every fourth year as a leap year, including all century years.

What happens to February 29 birthdays in common years?

People born on February 29 (“leaplings”) usually celebrate on February 28 or March 1 in common years. Legally, most jurisdictions treat March 1 as the day a leapling's age increments in a non-leap year.