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String.prototype.toLocaleUpperCase()

The toLocaleUpperCase() method returns the calling string value converted to upper case, according to any locale-specific case mappings.

Syntax

str.toLocaleUpperCase()

Return value

A new string representing the calling string converted to upper case, according to any locale-specific case mappings.

Description

The toLocaleUpperCase() method returns the value of the string converted to upper case according to any locale-specific case mappings. toLocaleUpperCase() does not affect the value of the string itself. In most cases, this will produce the same result as toUpperCase(), but for some locales, such as Turkish, whose case mappings do not follow the default case mappings in Unicode, there may be a different result.

Examples

Using toLocaleUpperCase()

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

Specifications

Specification Status Comment
ECMAScript 3rd Edition (ECMA-262) Standard Initial definition. Implemented in JavaScript 1.2.
ECMAScript 5.1 (ECMA-262)
The definition of 'String.prototype.toLocaleUpperCase' in that specification.
Standard  
ECMAScript 2015 (6th Edition, ECMA-262)
The definition of 'String.prototype.toLocaleUpperCase' in that specification.
Standard  
ECMAScript 2017 Draft (ECMA-262)
The definition of 'String.prototype.toLocaleUpperCase' in that specification.
Draft  

Browser compatibility

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari
Basic support (Yes) (Yes) (Yes) (Yes) (Yes)
Feature Android Chrome for Android Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile
Basic support (Yes) (Yes) (Yes) (Yes) (Yes) (Yes)

See also

Document Tags and Contributors

 Contributors to this page: eduardoboucas, fscholz, Mingun, Sheppy, Norbert, evilpie, Brettz9
 Last updated by: eduardoboucas,