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How Many Days Until Pi Day?
Sunday, March 14, 2027
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About Pi Day
Pi Day celebrates the mathematical constant π, the ratio of a circle's circumference to its diameter that begins 3.14159 and never ends. The date March 14 — written 3/14 in the US — matches those first digits, which is why mathematicians, teachers, students, and pastry enthusiasts around the world turn it into an annual party. It is one of the few holidays where dessert counts as homework.
Physicist Larry Shaw founded the celebration in 1988 at the Exploratorium science museum in San Francisco, where staff and visitors marched around a circular space and shared fruit pies. The idea spread quickly through classrooms worldwide, and in 2009 the US House of Representatives passed a nonbinding resolution recognizing the day. UNESCO went a step further in 2019, declaring March 14 the International Day of Mathematics. A happy coincidence adds star power: Albert Einstein was born on March 14.
What makes the day delightful is its mix of silliness and genuine learning. People compete to recite hundreds of digits of π, bake pies shaped like circles, run math scavenger hunts, and time their first bite to 1:59 PM so the moment reads 3.14159. In 2015, fans celebrated extra hard because 3/14/15 captured the first five digits.
History of Pi Day
Physicist Larry Shaw founded Pi Day in 1988 at the Exploratorium in San Francisco, where staff and visitors marched around a circular space and shared fruit pies. The date 3/14 was chosen because it matches π's opening digits, 3.14. The idea spread from museums to classrooms around the world, and in 2009 the US House of Representatives passed a nonbinding resolution recognizing the day. In 2019, UNESCO declared March 14 the International Day of Mathematics, giving the celebration official global standing. Pi Day also shares its date with Albert Einstein's birthday, a coincidence that fans happily exploit for themed parties. Stephen Hawking died on March 14 as well, giving the date a bittersweet footnote in science history.
2027 vs 2028 dates
Frequently Asked Questions
- When is Pi Day?
- Pi Day is celebrated on March 14 each year, because 3/14 matches the first three digits of π.
- Is Pi Day a public holiday?
- No, it is not a public holiday — it is an unofficial observance. Offices and schools stay open, though classrooms often join the fun.
- How do people celebrate Pi Day?
- People eat pie, hold digit-recitation contests, run math games, and mark the moment at 1:59 PM, when the clock reads 3.14159.
- Why is Pi Day on March 14?
- Because March 14 written numerically as 3.14 mirrors the opening digits of π.
- Who invented Pi Day?
- Physicist Larry Shaw started it in 1988 at the Exploratorium in San Francisco, and UNESCO later declared the date the International Day of Mathematics.