What Is the Rarest Birthday? 10 Rarest Birthdays in the U.S.

Happy birthday to you—and you and you! Wait a minute. Just how many people have the same birthday here? The answer may surprise you. According to the “birthday paradox,” in a random group of 23 people, there’s about a 50% chance that at least two people have the same birthday. And that’s the case whether they have one of the rarest birthdays or were born during the most popular birth month. But what is the rarest birthday of them all?

We have data on the dates and months with the fewest birthdays, and unlike presents, we’re not afraid to share them. Let’s be serious: Having a rare birthday is worth bragging about. So whether you’re a September baby, were born during March Madness or land anywhere in between, read on to find out where your birthday ranks.

What’s the rarest birth month?

According to data collected by the Centers for Disease Control and Prevention (CDC) and the Social Security Administration, the rarest birth month is February, making Aquarius the rarest zodiac sign. This makes logical sense—February is the shortest month of the year, even with a leap year.

Another factor that makes February a rare birth month: Conception would have happened in May, and when the weather is warmer and the days are longer, fewer babies tend to be conceived.

What are the rarest birthdays?

February babies are special, but what is the rarest birthday? Surprisingly enough, none of the rarest birthdays fall in February. Instead, many of them coincide with major holidays, such as Christmas Day, New Year’s Day and Christmas Eve. This is most likely due to the fact that there are fewer inductions and cesarean sections scheduled during the holidays.

These are the rarest birthdays in the United States, plus the average number of births on that day each year:

Dec. 25: 6,574 average yearly births
Jan. 1: 7,792 average yearly births
Dec. 24: 8,069 average daily births
July 4: 8,796 average yearly births
Jan. 2: 9,307 average yearly births
Dec. 26: 9,543 average yearly births
Nov. 27: 9,718 average yearly births
Nov. 23: 9,883 average yearly births
Nov. 25: 9,954 average yearly births
Oct. 31: 9,978 average yearly births

What’s the most common birth month?

August is not only the month of long sunny days and back-to-school bonanzas, but it’s also the most common birth month. The CDC data shows that July, August, September and October tend to be the most popular birth months in the United States, making the colder, cozier winter months the most popular time to conceive.

What are the most common birthdays?

While having one of the rarest birthdays can be pretty cool, having one of the most common birthdays is also a win—just think of all the people across the country celebrating too. And while August may be the most common birth month, almost all the most common birthdays happen to be in September.

Sept. 9: 12,301 average yearly births
Sept. 19: 12,229 average yearly births
Sept. 12: 12,224 average yearly births
Sept. 17: 12,148 average yearly births
Sept. 10: 12,144 average yearly births
July 7: 12,108 average yearly births
Sept. 20: 12,107 average yearly births
Sept. 15: 12,087 average yearly births
Sept. 16: 12,072 average yearly births
Sept. 18: 12,055 average yearly births

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