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Math.PI

The Math.PI property represents the ratio of the circumference of a circle to its diameter, approximately 3.14159:

Math.PI=π3.14159\mathtt{\mi{Math.PI}} = \pi \approx 3.14159

Property attributes of Math.PI
Writable no
Enumerable no
Configurable no

Description

Because PI is a static property of Math, you always use it as Math.PI, rather than as a property of a Math object you created (Math is not a constructor).

Examples

Using Math.PI

The following function uses Math.PI to calculate the circumference of a circle with a passed radius.

function calculateCircumference(radius) {
  return Math.PI * (radius + radius);
}

calculateCircumference(1);  // 6.283185307179586

Specifications

Browser compatibilityUpdate compatibility data on GitHub

Desktop
Chrome Edge Firefox Internet Explorer Opera Safari
PI 1 12 1 3 3 1
Mobile
Android webview Chrome for Android Firefox for Android Opera for Android Safari on iOS Samsung Internet
PI 1 18 4 10.1 1 1.0
Server
Node.js
PI 0.1.100

See also

© 2005–2018 Mozilla Developer Network and individual contributors.
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://wiki.developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Math/PI