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The slice() method extracts a section of a string and returns it as a new string, without modifying the original string.

Syntax

str.slice(beginIndex[, endIndex])

Parameters

beginIndex
The zero-based index at which to begin extraction. If negative, it is treated as strLength + (beginIndex) where strLength is the length of the string (for example, if beginIndex is -3 it is treated as strLength - 3). If beginIndex is greater than or equal to the length of the string, slice() returns an empty string.
endIndex
Optional. The zero-based index before which to end extraction. The character at this index will not be included. If endIndex is omitted, slice() extracts to the end of the string. If negative, it is treated as strLength + endIndex where strLength is the length of the string (for example, if endIndex is -3 it is treated as strLength - 3).

Return value

A new string containing the extracted section of the string.

Description

slice() extracts the text from one string and returns a new string. Changes to the text in one string do not affect the other string.

slice() extracts up to but not including endIndex. str.slice(1, 4) extracts the second character through the fourth character (characters indexed 1, 2, and 3).

As an example, str.slice(2, -1) extracts the third character through the second to last character in the string.

Examples

Using slice() to create a new string

The following example uses slice() to create a new string.

var str1 = 'The morning is upon us.', // the length of str1 is 23.
    str2 = str1.slice(1, 8),
    str3 = str1.slice(4, -2),
    str4 = str1.slice(12),
    str5 = str1.slice(30);
console.log(str2); // OUTPUT: he morn
console.log(str3); // OUTPUT: morning is upon u
console.log(str4); // OUTPUT: is upon us.
console.log(str5); // OUTPUT: ""

Using slice() with negative indexes

The following example uses slice() with negative indexes.

var str = 'The morning is upon us.';
str.slice(-3);     // returns 'us.'
str.slice(-3, -1); // returns 'us'
str.slice(0, -1);  // returns 'The morning is upon us'

This example counts backwards from the end of the string by 11 to find the start index and forwards from the start of the string by 16 to find the end index.

console.log(str.slice(-11, 16)) // => "is u";

Here it counts forwards from the start by 11 to find the start index and backwards from the end by 7 to find the end index.

console.log(str.slice(11, -7)) // => "is u";

These arguments count backwards from the end by 5 to find the start index and backwards from the end by 1 to find the end index.

console.log(str.slice(-5, -1)) // => "n us";

Specifications

Specification Status Comment
ECMAScript Latest Draft (ECMA-262)
The definition of 'String.prototype.slice' in that specification.
Draft  
ECMAScript 2015 (6th Edition, ECMA-262)
The definition of 'String.prototype.slice' in that specification.
Standard  
ECMAScript 5.1 (ECMA-262)
The definition of 'String.prototype.slice' in that specification.
Standard  
ECMAScript 3rd Edition (ECMA-262) Standard Initial definition. Implemented in JavaScript 1.2.

Browser compatibility

Update compatibility data on GitHub
DesktopMobileServer
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidEdge MobileFirefox for AndroidOpera for AndroidSafari on iOSSamsung InternetNode.js
sliceChrome Full support YesEdge Full support 12Firefox Full support 1IE Full support YesOpera Full support YesSafari Full support YesWebView Android Full support YesChrome Android Full support YesEdge Mobile Full support YesFirefox Android Full support 4Opera Android Full support YesSafari iOS Full support YesSamsung Internet Android Full support Yesnodejs Full support Yes

Legend

Full support  
Full support

See also