Math.PI

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

Math.PI = π 3.14159 \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 compatibility

Desktop Mobile
Chrome Edge Firefox Internet Explorer Opera Safari WebView Android Chrome Android Firefox for Android Opera Android Safari on IOS Samsung Internet
PI
1
12
1
3
3
1
1
18
4
10.1
1
1.0

See also

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Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Math/PI