String.prototype.trim()

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.

The trim() method of String values removes whitespace from both ends of this string and returns a new string, without modifying the original string.

To return a new string with whitespace trimmed from just one end, use trimStart() or trimEnd().

Try it

const greeting = "   Hello world!   ";

console.log(greeting);
// Expected output: "   Hello world!   ";

console.log(greeting.trim());
// Expected output: "Hello world!";

Syntax

trim()

Parameters

None.

Return value

A new string representing str stripped of whitespace from both its beginning and end. Whitespace is defined as white space characters plus line terminators.

If neither the beginning or end of str has any whitespace, a new string is still returned (essentially a copy of str).

Examples

Using trim()

The following example trims whitespace from both ends of str.

js
const str = "   foo  ";
console.log(str.trim()); // 'foo'

Specifications

Specification

ECMAScript® 2027 Language Specification
# sec-string.prototype.trim

Browser compatibility

Enable JavaScript to view this browser compatibility table.

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This page was last modified on Jul 10, 2025 by MDN contributors.

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Standard built-in objects
String
Constructor
1. String()
Static methods
Instance methods
Instance properties
1. length
Inheritance
Object/Function
Static methods
Static properties
Instance methods
Instance properties
1. __proto__
2. constructor