Pi Day is an annual American holiday dedicated to the number Pi. This mathematical phenomenon has long fascinated mathematical scientists around the world. It also has a “relative” – Euler’s number. These two values represent an infinite value in the digital record. The holiday is on March 14.

## History

For the creation of Pi Day, we have to thank physicist Larry Shaw, who saw that 3.14 (the approximate value of the number) in the entry 3/14 represents the date March 14. So why not dedicate the day to a mathematical phenomenon!

Researchers claim that the number Pi was known as far back as Ancient Babylon. It was used in the calculations for the construction of the Tower of Babel. However, the builders made a mistake somewhere, and the large-scale project was never erected. There is every reason to believe that this mathematical constant was used in the construction of the Temple of King Solomon.

The creator of the number Pi is considered to be the teacher W. Jones, who used it in his work A New Introduction to Mathematics. This event took place in 1706.

## Interesting facts

- In mathematical terms, the value of Pi is the ratio of the length of the circle to its diameter.
- There is a myth that the discoverer of Pi is L. Euler. However, this is not the case. William Jones published it in his book a year before Euler discovered the number.
- The number Pi has been repeatedly played up in literature and film. We recommend reading C. Sagan’s novel “Contact,” where the characters tried to unravel the secret of this number to receive messages from the creators of the human race.

## How to celebrate

Solve math problems using the number Pi on this day. Learn more interesting information about the constant on Pi Day. Celebrate the holiday in culinary style. Bake a round cake or make a pie in the shape of a circle, decorating it with the Pi symbol on top.

Spread the word on social media. Let more people know about Pi Day!

## When is National Pi Day in 2025?

National Pi Day is observed on March 14 each year.

### Observations

Weekday |
Month |
Day |
Year |

Friday | March | 14 | 2025 |

Saturday | March | 14 | 2026 |

Sunday | March | 14 | 2027 |

Tuesday | March | 14 | 2028 |

Wednesday | March | 14 | 2029 |