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The toLowerCase() method returns the calling string value converted to lower case.

Syntax

str.toLowerCase()

Return value

A new string representing the calling string converted to lower case.

Description

The toLowerCase() method returns the value of the string converted to lower case. toLowerCase() does not affect the value of the string str itself.

Examples

Using toLowerCase()

console.log('ALPHABET'.toLowerCase()); // 'alphabet'

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 'String.prototype.toLowerCase' in that specification.
Standard  
ECMAScript 2015 (6th Edition, ECMA-262)
The definition of 'String.prototype.toLowerCase' in that specification.
Standard  
ECMAScript Latest Draft (ECMA-262)
The definition of 'String.prototype.toLowerCase' 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
toLowerCaseChrome 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 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

文件標籤與貢獻者

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