Math.cos()

The Math.cos() static method returns the cosine of a number in radians.

{{InteractiveExample("JavaScript Demo: Math.cos()")}}

```js interactive-example function getCircleX(radians, radius) { return Math.cos(radians) * radius; }

console.log(getCircleX(1, 10)); // Expected output: 5.403023058681398

console.log(getCircleX(2, 10)); // Expected output: -4.161468365471424

console.log(getCircleX(Math.PI, 10)); // Expected output: -10

## Syntax

```js-nolint
Math.cos(x)

Parameters#

• x
• : A number representing an angle in radians.

Return value#

The cosine of x, between -1 and 1, inclusive. If x is {{jsxref("Infinity")}}, -Infinity, or {{jsxref("NaN")}}, returns {{jsxref("NaN")}}.

Description#

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(-Infinity); // NaN
Math.cos(-0); // 1
Math.cos(0); // 1
Math.cos(1); // 0.5403023058681398
Math.cos(Math.PI); // -1
Math.cos(2 * Math.PI); // 1
Math.cos(Infinity); // NaN

Specifications#

{{Specifications}}

Browser compatibility#

{{Compat}}

See also#

• {{jsxref("Math.acos()")}}
• {{jsxref("Math.asin()")}}
• {{jsxref("Math.atan()")}}
• {{jsxref("Math.atan2()")}}
• {{jsxref("Math.sin()")}}
• {{jsxref("Math.tan()")}}
• CSS {{cssxref("cos()")}} function