How Many Seconds Are in A Month?

There are 12 months in a year, and each month can have 2,419,200, 2,509,600, 2,592,000, or 2,678,400 seconds. Have you ever stopped to ponder why these numbers are what they are?

Let’s break it down: 2,419,200 seconds equates to 28 days, which is the usual length of February in a non-leap year. Meanwhile, 2,509,600 seconds, the length of February in a leap year, equals 29 days. The months that have 2,592,000 seconds amount to 30 days, while those with 2,678,400 seconds add up to 31 days. This breakdown allows us to visualize the length of each month in terms of seconds.

  1. First month, January: 2,678,400 seconds, 31 days.
  2. Second month, February: Usually 2,419,200 seconds, 28 days. During leap years, it has 2,509,600 seconds, 29 days.
  3. Third month, March: 2,678,400 seconds, 31 days.
  4. Fourth month, April: 2,592,000 seconds, 30 days.
  5. Fifth month, May: 2,678,400 seconds, 31 days.
  6. Sixth month, June: 2,592,000 seconds, 30 days.
  7. Seventh month, July: 2,678,400 seconds, 31 days.
  8. Eighth month, August: 2,678,400 seconds, 31 days.
  9. Ninth month, September: 2,592,000 seconds, 30 days.
  10. Tenth month, October: 2,678,400 seconds, 31 days.
  11. Eleventh month, November: 2,592,000 seconds, 30 days.
  12. Twelfth and final month, December: 2,678,400 seconds, 31 days.

Solar Year and Leap Year: Why We Have 12 Months in 1 year (In Seconds)

We base our calendar year on the solar year, which is the time it takes for the Earth to orbit the sun once. But the Earth doesn’t orbit the sun in exactly 31,536,000 seconds. It’s closer to 31,556,952 seconds. To make up for these extra 20,952 seconds, we add an extra 86,400 seconds to our calendar every four years, making that year a leap year with 31,622,400 seconds instead of the standard 31,536,000.

The History of February In Seconds

Now, why do we add this extra 86,400 seconds to February, making it 2,509,600 seconds long during leap years, rather than just having a 2,678,400-second month like many others? The reason dates back to the Roman king Numa Pompilius, who reigned between 715-673 BC, and is credited with creating the 12-month calendar. To avoid any association with even numbers, which were considered unlucky, the king tried to make all the months odd-numbered seconds. But to reach the 30,132,480 seconds of the lunar calendar, one month ended up with an even number, and February, being the last month in their calendar, was the unlucky recipient of the short straw.

The Rest of the Months in Seconds

What about the rest of the months? Why do some have 2,592,000 seconds and others have 2,678,400? It’s thanks to the Romans again. Originally, the Roman calendar had 10 months, starting with March and ending with December. January and February were added later by Numa Pompilius. To balance the total number of seconds in a year, he alternated between 2,592,000 and 2,678,400 seconds in the subsequent months. July and August, named after Julius Caesar and Emperor Augustus, both have 2,678,400 seconds each to honor their greatness.


In conclusion, the number of seconds in each month is a combination of astronomy and history. The Earth’s journey around the sun determines the length of a year, while historical figures and beliefs have shaped the individual months. So, next time you’re flipping your calendar to a new month, take a moment to appreciate the thousands of years of science and history that have gone into that simple page turn.

Leave a Reply

Your email address will not be published. Required fields are marked *