I recently celebrated a birthday and was surprised to learn that I knew three other women in my town who shared the same birthdate.

Since our area is relatively small, it got me wondering…

• How popular is my birthday?
• What is the most popular birthday?

Thanks to Matt Stiles at The Daily Viz (a huge shout out for this really cool site that finds stories hidden with reams of data; viz is short for visualization), I got my birthday-related questions answered and so can you.

Matt analyzed 20 years worth of US average daily births and then turned it into a gorgeous interactive heat map that allows you to search by date to see just how popular your birthday is.

The site also offers an estimate of conception day for each birth date...which you may want to use cautiously.  I started down this path, and before I knew it, I was imagining the specific scenario....and well, I think we can all agree that no one wants to think of their parents having sex!

Impress Your Friends With 3 Fun Birthday Trivia 

Here's some trivia you might be interested to know:

1. The most common birthday in America is September 9th, which happens to be this Sunday.  

2. The second most common birthday is September 19th.
The least common birthdays are

• December 24th (#364 in popularity)
• January 1st  (#365)
• December 25th  (#366)

…which likely is because most doctors would prefer to be enjoying their holidays instead of delivering babies.

3. September is the most popular month for birthdays.  

In fact, 9 out of 10 of the most popular birth dates occur between September 9th and September 20th.

If you check out the conception dates for these birthdates, it’s easy to conclude that people are feeling very warm and cozy in mid to late December.  Perhaps there’s something to that mistletoe.   ;)

Relatively speaking, you are ~87% more likely to meet someone born on the most popular day (September 9) vs. the least popular day (December 25th).  
This surprised me because I don’t know anyone born on September 9th, but I do know several people born on Christmas. My guess is that the Christmas birthdays (such as the truly joyous JeanAnn Nichols, the most positive person I’ve ever met and a kickass executive coach and speaker) stand out in my mind.

Birthday Trivia Makes a Fun Party Game, Especially for an Adult Celebration

To make this more actionable, consider:

1. Checking out the popularity of your birthdate (I'm #31!).
2. Look into how common family and friends' birthdates are
3. Double check out your calendar for any upcoming September birthdays.  It’s likely you know someone who will be celebrating.
4. Using this birthday trivia as a party game.  

No matter when you were born, it's quite likely your family thought you were the most beautiful baby in the world.  Remember that the next time your parents ask you to do something for them.