3.14 Facts: Everything You Need to Know for Pi Day 2026

Pi Day is an annual celebration of the mathematical constant π (pi). Pi Day is observed on March 14 (the 3rd month) since 3, 1, and 4 are the first three significant figures of π, and was first celebrated in the United States.

History and Significance

The Physicist Larry Shaw founded Pi Day in 1988 at the Exploratorium in San Francisco.

The U.S. House of Representatives passed a resolution in 2009 officially designating March 14 as National Pi Day. Pi Day coincides with the birthday of Albert Einstein (born March 14, 1879), adding a scientific layer to the festivities.

It is the ratio of a circle’s circumference to its diameter (). It is an irrational and transcendental number, meaning its digits go on forever without repeating.

Common Ways to Celebrate

• Eating Pie: Because “pi” and “pie” are homophones and pies are circular, consuming fruit pies, pizza pies, or pot pies is the most popular tradition.
• Memorization Contests: Enthusiasts compete to see who can recite the most digits of . The current Guinness World Record is held by Rajveer Meena, who recited 70,000 digits in 2015.
• Pi Processions: Many schools and museums, like the Exploratorium, hold parades where people walk in circles  times.
• Special Times: Some celebrations peak at 1:59 p.m. to match the next three digits of pi ().
• Physical Activities: People participate in “Pi Runs” of  miles (roughly  km).

Alternative “Pi” Days

• Pi Approximation Day: Observed on July 22 (), as the fraction  is a common approximation for π.
• Tau Day: Celebrated on June 28 () to honor the constant  (), which equals to 2π.

Would you like some math-themed riddles or a recipe for a specific type of pie to bake for your celebration?