Today is Pi Day for 2026, the universal celebration of an amazing, mysterious, and irrational mathematical constant. What's ...

Explore the origins of Pi Day from San Francisco's Exploratorium to global recognition, blending math, culture, and pie in a ...

Best known as Pi Day, 3/14 is the celebration of the number that begins with 3.14159 … and never ends. Pi (π) is the ratio of a circle’s circumference to its diameter. Or, in other words, just divide ...