Math.cos

The Math.cos() function returns the cosine of a number.

Syntax

Math.cos(x)

Parameters

x

A number given in unit of radians.

Return value

The cosine of the given number.

Description

The Math.cos() method returns a numeric value between -1 and 1, which represents the cosine of the angle.

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

Examples

Using Math.cos()

Math.cos(0);           // 1
Math.cos(1);           // 0.5403023058681398

Math.cos(Math.PI);     // -1
Math.cos(2 * Math.PI); // 1

Specifications

Specification	Status	Comment
ECMAScript 1st Edition (ECMA-262)	Standard	Initial definition. Implemented in JavaScript 1.0.
ECMAScript 5.1 (ECMA-262) The definition of 'Math.cos' in that specification.	Standard
ECMAScript 2015 (6th Edition, ECMA-262) The definition of 'Math.cos' in that specification.	Standard
ECMAScript 2017 Draft (ECMA-262) The definition of 'Math.cos' in that specification.	Draft

Browser compatibility

See also

• Math.acos()
• Math.asin()
• Math.atan()
• Math.atan2()
• Math.sin()
• Math.tan()