The number π (/ paɪ / ⓘ; spelled out as pi) is a mathematical constant, approximately equal to 3.14159, that is the ratio of a circle 's circumference to its diameter.

1 Million Digits of Pi The first 10 digits of pi (π) are 3.1415926535 The first million digits of pi (π) are below. Why not calculate the circumference of a circle using pi here. Or simply learn about …

Jun 20, 2025 · pi, in mathematics, the ratio of the circumference of a circle to its diameter. The symbol π was devised by British mathematician William Jones in 1706 to represent the ratio …

Draw a circle with a diameter (all the way across the circle) of 1. Then the circumference (all the way around the circle) is 3.14159265... a number known as Pi. Pi (pronounced like "pie") is …

May 17, 1999 · Succinctly, pi—which is written as the Greek letter for p, or π—is the ratio of the circumference of any circle to the diameter of that circle. Regardless of the circle's size, this …

Sep 21, 2023 · What Is Pi? Pi is a circle's circumference divided by its diameter. (The diameter is twice the radius or double the length from any point on the circle to its center. The …

The greek small letter π (pi) is a geometric constant approximately equal to 3.1416. The numeric value is equal to the length of any circle's circumference divided by its diameter.

It is defined as the ratio of a circle's circumference to its diameter, and it also has various equivalent definitions. It appears in many formulas in all areas of mathematics and physics. It …

Discover what pi means in math, why it’s written as π, how to use it for circles and spheres, and why it continues to amaze mathematicians.

Pi: Directed by Darren Aronofsky. With Sean Gullette, Mark Margolis, Ben Shenkman, Pamela Hart. A paranoid mathematician searches for a key number that will unlock the universal …