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February has 29 days this year

Photo: Michael Bihlmayer / Bihlmayerfotografie / IMAGO

Why are there leap years?

Every four years the year is extended by one day, February then has 29 days instead of 28.

The reason for the extension of the month is simple: our Earth needs exactly 365 days, 5 hours, 48 ​​minutes and 46 seconds to orbit the sun.

A solar year is therefore almost a quarter of a day longer than a calendar year.

However, because the calendar can only consist of whole days, the additional time must be compensated.

To ensure this, an additional day is added every four years.

Or to put it another way: A year usually starts almost six hours early.

Over a year, the difference is hardly significant.

But if one were to forego the leap year, the calendar would be a whole day too early after four years, and even a whole month too early after a hundred years.

If this continues forever, July would soon be the depths of winter.

If you've been paying attention, you'll have noticed that the year isn't


six hours too long.

The little trick with the leap year only mitigated the "calendar deviation"; every 120 years there would still be one missing day.

The makers of our calendar also understood this and set up two additional rules:

  • No “smooth” hundred year can be a leap year: This reduces the calendar error to one missing day every 457 years.

  • Excepted from this are all years that can be easily divided by the number 400: This reduces the calendar deviation to one missing day every 3225 years.

What is it like in other cultures?

There are leap years in


too .

The Islamic lunar calendar - consisting of 354 days - has the same problem as our solar calendar - the lunar year is not exactly 354 days long, but 354.37 days.

That's why every now and then a leap day is inserted according to a very complicated rule.

However, having a month with exactly 29 days is completely normal for Muslims: it happens every other month.

This also explains why Ramadan moves on the calendar.

But things only get really complicated in



There, solar and lunar calendars are combined (the lunisolar year).

By design, it is actually a lunar calendar, but it is synchronized with the solar year using a trick.

This trick is called the Meton cycle - and nothing makes it clearer how wonderfully uncomplicated our leap year regulation really is.

Because you can't get by with leap days in the Jewish calendar, they have to be whole leap months.

The Meton cycle combines 19 years, twelve of which comprise twelve months each, and the remaining seven comprise 13 months.

Years with 12 months are between 353 and 356 days long, while years with 13 months are between 383 and 385 days long.

As mentioned before, it's complicated (learn more about that here).

What happens if my birthday is on February 29th?

People whose birthday is on February 29th can be happy: this year they can celebrate on their actual birthday.

In non-leap years this is usually postponed to March 1st.

From a purely legal perspective, this day is also considered significant, for example when it comes to criminal responsibility, legal capacity or coming of age.

Why can employers be happy about leap years?

Sure, an extra day in the year often results in an extra day of work.

Employers are particularly happy about this.

But in 2024, holidays and weekends are particularly favorable for employees.

Therefore, the German economy, which is threatened by recession, cannot count on any economic tailwind.

According to the Federal Statistical Office, there will be an average of 248.8 working days nationwide in 2024 - despite the leap year, that is 0.6 days fewer than in the previous year.

"This is because public holidays, festival days such as Christmas Eve and New Year's Eve, but also weekends are different than in 2023," it said.

In the current first quarter, despite the leap year, there are 1.6 fewer working days on average across the country than a year ago, due to the early Easter holidays.

This will also dampen the development of the gross domestic product (GDP) in the first quarter.

And otherwise?

There are always strange events around the leap year.

For example, 1582 was the shortest year in contemporary history.

Back in the 16th century, the

Gregorian calendar

(named after Pope Gregory XIII) was introduced.


In order for this to be compatible with the new leap day rule, ten days had to be canceled.

So October 4th was followed by October 15th.

The city of Anthony in the US state of Texas calls itself the capital of the leap year.

The special event around February 29th is used for a four-day party, which can be attributed to

Mary Ann Brown and Birdie Lewis


Both had their birthdays on February 29th and decided to make a big celebration of it at the end of the 1980s.

In Greece, many people are rather skeptical about upcoming leap years.

This is one of the reasons why people who want to get married line up at the end of December to say their vows.