Why Does February Only Have 28 Days?

(Last Updated On: February 7, 2020)
Why Does February Only Have 28 Days?

If you take a look at a calendar for any given year, you’re going to see a few unique quirks. However, one of the strangest items that might stand out is the fact that February only lasts 28 days… unless it’s a leap year. On leap years, February has one extra day, which arguably makes February even stranger

So what makes February so different? An interesting historical tale, that’s what. So, buckle up, here’s all you need to know.

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Why Does February Only Have 28 Days?

We owe our modern calendar system to the Ancient Romans. You may have heard that Emperor Augustus took a day from February (which had 29 days) to give to August, the month named for him. However, that story is just a common myth.

In fact, the real reason is that February and January weren’t original months in the Roman calendar. The ancient Romans originally worked with a 10-month calendar, that started with the spring equinox in March and ended in December. A year in this calendar had just 304 days. 

At this point, you may be confused. How do you get along with a year that’s only 304 days long? Again, we need to look back at the ancient purposes of the calendar, which were primarily to help farmers plan out their planting and harvesting schedule. The winter months didn’t have much use for them, so this time of year simply didn’t exist on the calendar.

While a 304-day year was the norm for a while, this changed during the reign of Numa Pompilius, the second king of Rome. He wanted a calendar that encompassed the entire year, so in 713 BC, he created a new one that aligned with the lunar cycle, which is roughly 355 days long.

However, since the year was now longer, there was a need for new months, so two new ones were added to the end of the calendar. All 12 months in this calendar had either 31 or 29 days, except for the last month, Februarius, which was 28 days long.

So, why is February shorter than the rest? A combination of superstition and a bit of laziness, most likely. In Rome, even numbers were considered unlucky, so Pompilius wanted all of the months to contain an odd number of days (thus 29 and 31). However, this couldn’t happen if they wanted a total of 355 days. February was the last month on the list, which is likely why it got stuck with this designation. 

The Origins of Leap Years

So, wondering why we don’t have 355 days in a year today? After a few years of this new model, issues started arising with months and seasons becoming desynchronized. With the harvest cycle dependent on the calendar, this posed a major issue. To try and simplify things, the Romans created a leap month that lasted 27 days–Mercedonius. However, this also led to tons of issues, mainly due to inconsistency. The Roman high priests were in charge of implementing leap months, but they ended up doing it poorly, and even exploiting it for political gain.

It was Julius Caesar who ended up seizing the reins of the wayward calendar and getting things working properly. To give you an idea of how out of control things had gotten, 46 BCE in Rome was 445 days long! 

Rather than lunar cycles, Caesar focused on the sun, and added some days to the calendar to get to 365. However, because the earth goes around the sun every 365.242 days, in time, this would lead to the calendar eventually getting out of sync again. Caesar prepared for this, and with the help of his astronomers, added a 4th day to February every 4 years, creating the leap year. This would then be changed slightly in 1582 by Pope Gregory XIII, creating the rule that a leap day would occur in a year divisible by 4.

Further reading: What Is a Leap Year?

Okay, so you know why February only has 28 days. But how much more do you know about the calendar? Test yourself with the fun quizzes below!