February 29 is the rarest date on the calendar. Leap Day comes around only in leap years, roughly once every four years, and it exists to keep our calendar in step with Earth's orbit around the sun. People born on February 29, often called 'leaplings', only see their real birthday every few years. The next leap days are in 2028 and 2032, so when Leap Day does arrive, it feels like a bonus day worth celebrating.
History of Leap Day
A year on Earth, the time it takes to orbit the sun, is about 365.2422 days, not exactly 365. Without adjustments, the calendar would slowly drift away from the seasons.
In 46 BC, Julius Caesar introduced the Julian calendar, which took effect in 45 BC and added an extra day every four years. But this overcorrected slightly, because a year is a little less than 365.25 days. Over centuries, the calendar drifted by about 10 days.
In 1582, Pope Gregory XIII introduced the Gregorian calendar, which fixed the problem with a new rule: a year is a leap year if it is divisible by 4, except century years, which must also be divisible by 400. So 2000 was a leap year, but 1900 was not, and 2100 will not be. Britain and its American colonies adopted the Gregorian calendar in 1752.
Folk traditions grew around the day. In Ireland and Britain, an old custom held that women could propose marriage on February 29, a tradition sometimes linked to a legend about St. Bridget and St. Patrick.
Why Leap Day Matters
Leap Day keeps the calendar aligned with the seasons, which matters for farming, holidays and daily life.
It is also a fun, rare occasion. People use it to do something new, since it is literally an extra day.
How to Celebrate Leap Day
- Do something new: use the bonus day to try a new activity.
- Celebrate leaplings: wish anyone born on February 29 a happy real birthday.
- Learn the math: work out which years are leap years.
- Make a time capsule: open it on the next Leap Day.
- Jump around: hold a leapfrog game or jumping contest for fun.
Celebrating at Work, School and Home
At work, teams can use the extra day for a 'bonus day' activity, such as learning a new skill, volunteering or tackling a long-postponed project. In classrooms, Leap Day is perfect for math and science lessons on Earth's orbit, calendars and divisibility rules; students can calculate which years are leap years or write letters to their future selves to open in four years. At home, families can create a time capsule, plan a special Leap Day dinner, or celebrate any leapling relatives with a big party. In non-leap years, leap-day babies usually celebrate on February 28 or March 1.
Fun Facts About Leap Day
- A solar year is about 365.2422 days long.
- Century years are only leap years if divisible by 400, so 2000 was a leap year but 1900 was not.
- The next leap days are in 2028 and 2032.
Leap Day FAQs
When is Leap Day?
February 29, which only occurs in leap years. The next are 2028 and 2032.
Why do we have leap years?
Because Earth takes about 365.24 days to orbit the sun, an extra day keeps the calendar aligned with the seasons.
How do I know if a year is a leap year?
It must be divisible by 4; century years must also be divisible by 400.
When do people born on February 29 celebrate?
Usually on February 28 or March 1 in non-leap years.