Math.tan()

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The Math.tan() function returns the tangent of a number.

Syntax

Math.tan(x)

Parameters

x
A number representing an angle in radians.

Return value

The tangent of the given number.

Description

The Math.tan() method returns a numeric value that represents the tangent of the angle.

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

Examples

Using Math.tan()

Math.tan(1); // 1.5574077246549023

Because the Math.tan() function accepts radians, but it is often easier to work with degrees, the following function accepts a value in degrees, converts it to radians and returns the tangent.

function getTanDeg(deg) {
  var rad = deg * Math.PI/180;
  return Math.tan(rad);
}

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.tan' in that specification.
Standard  
ECMAScript 2015 (6th Edition, ECMA-262)
The definition of 'Math.tan' in that specification.
Standard  
ECMAScript Latest Draft (ECMA-262)
The definition of 'Math.tan' in that specification.
Draft  

Browser compatibility

Update compatibility data on GitHub
DesktopMobileServer
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidFirefox for AndroidOpera for AndroidSafari on iOSSamsung InternetNode.js
tanChrome Full support 1Edge Full support 12Firefox Full support 1IE Full support 3Opera Full support YesSafari Full support YesWebView Android Full support 1Chrome Android Full support 18Firefox Android Full support 4Opera Android Full support YesSafari iOS Full support YesSamsung Internet Android Full support 1.0nodejs Full support Yes

Legend

Full support  
Full support

See also