What Is Pi Day, and When Is It Celebrated?

February 15, 2023

What Is Pi Day, and When Is It Celebrated?

Pi is the ratio of a circle's circumference to its diameter – apple pie is a delicious pastry that comes in many different shapes and flavors.So, why do we celebrate one and not the other?

Well, it turns out you can celebrate all types of Pi(e) on Pi Day. From strawberry pie & pizza pie to those first digits of our favorite irrational number, Pi has been long celebrated as one of the most important symbols and discoveries in mathematical history.

What the Heck Is National Pi Day?

The Greek letter “π” is a symbol that represents the mathematical constant Pi (circle's circumference to diameter), which comes out to around 3.14159 – give or take a few. There are over 50 trillion digits of Pi, which continues infinitely without repetition or pattern.

The first Pi Day was run and celebrated by physicist Larry Shaw, who was the first to connect March 14th to the famous symbol. He held the event at San Francisco Exploratorium with fruit pies and tea in 1988.

In 2009, the House of Representatives officially marked March 14 asNational Pie Day.Shaw would continue to lead Pi Day celebrations and parades until his passing in 2017.

Why all the focus on the symbol? Well, for starters: it's ancient! Ancient Greek mathematician Archimedes is credited with first calculating the estimated value of Pi.

We have him to thank for discovering a mathematical constant that has been crucial to the engineering world, as it made modern construction possible all because of what those first three digits (and the other 50 trillion) represent to the constant circumference of a circle's diameter.

Celebrations often include consuming fruit pies or having pi reciting contests. Just like a writer needs to perform spoken word poems, lovers of pi recite as many digits of the beautiful symbol as possible.

As for the consumption of pies, most math nerds gravitate towards the basics: apple, strawberry, rhubarb, and cherry pie are some of the most popular pies to chow down on Pi Day.

The significance of March 14th goes beyond Pi Day – it's also Albert Einstein's birthday! Pi Day celebrations run side by side on the renowned scientist's birthday, a delight to math lovers everywhere. So, in between the numbers of Pi, everyone leaves a little room for a round of "Happy Birthday" to commemorate another wonder of the mathematics world.

Celebrating the Mathematical Constant Pi

Okay, we know we said we had 3.14 ways to celebrate Pi Day, but we felt that was a little short (great math joke, though). Instead, we found 5 ways to celebrate National Pi Day that will get your calculator running!

  1. Enjoy a slice of pizza pie
    As we always say: when the math hits your eye like a big pizza pie, that's Pi Day! Grab a couple of large pizzas from your favorite local pizza place and place bets on their circumference.
    We're sure some of your math buddies would be over-eager to use Pi while eating their pizza pie! Whether you're craving pepperoni, Hawaiian, or just plain cheese, a pizza pie is never a wrong move on Pi Day.
  2. Host a Pi reciting contest
    Public speaking can be scary, but math enthusiasts agree that numbers are easier than words. Hold a contest where anyone who can recite the most digits of Pi gets to take home a special Pi Day-themed prize.
    Host a Pi Day pre-party and strategize ways to memorize the most digits of Pi in the shortest amount of time. Start with the first digit, obviously, and work from there.
    Ten-year-old Alexander Jin was added to the Pi World Ranking list after listing the first 282 digits of Pi. He did this by memorizing the numbers in chunks of six – his strategy could also work for you!
  3. Eat foods that start with Pi
    Bring joy this Pi Day with a feast of foods from around the world. The only rule is: they have to start with Pi! Here's a list of some different foods and meals that could be on your menu on March 14th:
  • Pie (duh).
  • Pizza.
  • Pineapple.
  • Pita bread.
  • Piccini rolls.
  • Pinto beans.
  • Pistachios.
  • Pickles.
  • PineBerry.
  • Pigface fruit.
  • If you wanted to get even crazier, you could only eat circular Pi foods and use pi to measure their circumference and diameter before you chow down. Keep your stomach and brain full this Pi Day, and celebrate big!
  • Run a circle's circumference (3.14 miles!)
    Getting your sweat on is a great way to celebrate any holiday, and unlike a traditional Thanksgiving run, you won't be too full from turkey to move!
    Grab your water bottle and favorite running shoes because running 3.14 miles is no joke. Be sure to include a Pi Day prize as an incentive – maybe some real-life pies and a cool medal?
    If you'd like to raise money for your favorite charity, why not charge a $3.14 entrance fee and support a great cause?
  • Rock some sweet Pi Day merchandise!
  • AtFamous In Real Life, we know how much of an impact a good Pi Day celebration can have on the math world. So, on National Pi Day, we want to offer you a free slice of advice – rock your Pi Day memorabilia!
  • Check out our favorite Pi Day shirts, sure to have made even Albert Einstein crack a smile.

Pumpkin Pie T-Shirt

Pumpkin Pi T-Shirt

Want to get spooky and smart this Pi Day? Although Halloween is a little far away from March 14th, there's nothing wrong with celebrating early in this versatile holiday tee.

Pizza Pie T-Shirt

Pizza Pi T-Shirt

A traditional Pi Day classic. Show off your love of great food and even greater geekdom with this cheesy tee. Be sure to get a photo of yourself eating a slice of pizza the size of your face while wearing it!

Cherry Pie T-Shirt

Cherry Pi T-Shirt

Tastes so good it'd make a grown mancry! Cherry pie might not be for everyone, but this gorgeous red fruit represents your love of the underdog.

Apple Pie T-Shirt

Apple Pi T-Shirt

Nothing beats a classic. Remember the smell of Grandma's kitchen during the cold autumn months? How did she always let you have the first piece of pie before anyone else? Nostalgia is a beautiful thing, and you should wear it proudly.

Slice of Pi T-Shirt

Slice Of Pi T-Shirt

Cut yourself a slice of life this Pi Day and put it on your t-shirt. Pi INSIDE a pie – pieception, anybody?

Life's a Slice

Celebrating Pi Day is as easy as...well, pie! Enjoy nerding out over everyone's favorite number and stuff your face full of every type of pie imaginable. The hardest choice you'll have to make on March 14th will be between apple and pumpkin.


Pi Day T-Shirts

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