Web/JavaScript/Reference/Global objects/String/trim

The trim() method removes whitespace from both ends of a string. Whitespace in this context is all the whitespace characters (space, tab, no-break space, etc.) and all the line terminator characters (LF, CR, etc.).

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Syntax

str.trim()

Return value

A new string representing the str stripped of whitespace from both ends.

Description

The trim() method returns the string stripped of whitespace from both ends. trim() does not affect the value of the str itself.

Polyfill

Running the following code before any other code will create trim() if it's not natively available.

if (!String.prototype.trim) {
  String.prototype.trim = function () {
    return this.replace(/^[\s\uFEFF\xA0]+|[\s\uFEFF\xA0]+$/g, '');
  };
}

Examples

Using trim()

The following example displays the lowercase string 'foo':

var orig = '   foo  ';
console.log(orig.trim()); // 'foo'

// Another example of .trim() removing whitespace from just one side.

var orig = 'foo    ';
console.log(orig.trim()); // 'foo'

Specifications

Specification
ECMAScript (ECMA-262)The definition of 'String.prototype.trim' in that specification.

Browser compatibility

The compatibility table in this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.

Update compatibility data on GitHub

	Desktop						Mobile						Server
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet	Node.js
trim	Chrome Full support 4	Edge Full support 12	Firefox Full support 3.5	IE Full support 9	Opera Full support 10.5	Safari Full support 5	WebView Android Full support ≤37	Chrome Android Full support 18	Firefox Android Full support 4	Opera Android Full support 11	Safari iOS Full support 5	Samsung Internet Android Full support 1.0	nodejs Full support 0.1.100

Legend

Full support  

Full support

See also

• String.prototype.trimStart()
• String.prototype.trimEnd()

String.prototype.trim() by Mozilla Contributors is licensed under CC-BY-SA 2.5.