What is a leap year

A leap year (also known as an intercalary year or bissextile year) is a calendar year that contains an additional day. This extra day is added to keep the calendar year in sync with the astronomical year or seasonal year which in itself is determined by astronomical events, namely the rotation of the Earth around the Sun. Calendars that have a constant number of days in each year (e.g. 365 for the Gregorean calendar) would exhibit a drift relative to these events if not for the extra day roughly every four years. For example, without leap years the beginning of the winter season in the Northern hemisphere would slowly shift and no longer be on Dec 21-22.

The term “leap year” probably comes from the fact that typically, in a leap year, the day of the week on any given date would shift by skipping one day. E.g. Christmas Day (December 25) would fall on advancing days of the week each year: Monday, Tuesday… However, on a leap year it will skip a day. For example, instead of Wednesday it would fall on Thursday, as would happen in the year 2024 of the Gregorian calendar system.

What is the next leap year?

The next leap year of the Gregorian calendar is the year 2024. In 2024, there will be Summer Olympic games in Paris starting on Jul 26. There will also be a UEFA Euro 2024 football championship (soccer, as it is also known in the U.S.). In the United States there will be a Presidential election – the 60th quadrennial presidential election to be precise.

 How to check if a given year is a leap year

While there is no leap year formula, there is a simple algorithm that can be followed to determine if a given year is a leap year or a common year. The algorithm consists of the following steps:

1. Check if the year can be divided by 4 without a remainder. If it cannot, it is not a leap year. Otherwise, proceed to (2).
2. Check if the year can be divided by 100 without a remainder. If it cannot, then it is a leap year. Otherwise, proceed to (3).
3. Check if the year can be divided by 400 without a remainder. If it cannot, then it is not a leap year. Otherwise, it is a leap year.

A division without a remainder is also called “evenly divisible”. E.g. from the above rule we can see that if a year is not evenly divisible by 4, it is a common year.

If you find the above steps difficult to follow, just use our calculator to easily perform a leap year check. It is also super useful if you need to compute the number of leap years in a period, or to get a list of all leap years in a given time range.

 List of leap years

These are all leap years between the years 1900 and 2050:

1904, 1908, 1912, 1916, 1920, 1924, 1928, 1932, 1936, 1940, 1944, 1948, 1952, 1956, 1960, 1964, 1968, 1972, 1976, 1980, 1984, 1988, 1992, 1996, 2000, 2004, 2008, 2012, 2016, 2020, 2024, 2028, 2032, 2036, 2040, 2044, 2048

To get a leap year list for any time period, just use the leap year calculator in the respective mode.