National Day

National Pi Day

Celebrated on 03/14/2026

Quick Fact

National Pi Day is celebrated on March 14 (3/14) because the date's digits match the first three digits of π (3.14). The holiday was first officially recognized by the U.S. House of Representatives in 2009, and it is often marked by eating pie and engaging in math-related activities.

Origins and Establishment of National Pi Day

National Pi Day was first celebrated in 1988 at the San Francisco Exploratorium, a science museum, by physicist Larry Shaw. Shaw and his colleagues organized a circular parade and ate fruit pies to commemorate the mathematical constant π. The idea gained popularity through the years, and in 2009, the U.S. House of Representatives passed a resolution (H.Res. 224) officially designating March 14 as National Pi Day. The resolution encouraged schools and educators to observe the day with activities that teach students about π and promote interest in mathematics.

Evolution and Modern Commemoration

Over time, National Pi Day has evolved from a small museum event into a global celebration. Schools, universities, and math enthusiasts now host events such as pie-eating contests, π recitation competitions, and math puzzles. The day has also become a marketing opportunity for restaurants and bakeries offering discounted pies. In 2015, the day was especially significant because the date (3/14/15) matched the first five digits of π (3.1415). Today, the holiday is recognized worldwide, often combined with Albert Einstein's birthday (also March 14) to add a layer of scientific appreciation.

Facts & General Observations

  • The record for the most digits of π memorized is held by Rajveer Meena of India, who recited 70,030 digits in 2015.
  • The symbol for π (π) has been used in mathematics for over 250 years, first introduced by Welsh mathematician William Jones in 1706.
  • The Exploratorium in San Francisco continues to host an annual Pi Day celebration, featuring a circular parade and pie-eating contests.

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