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The toUpperCase() method returns the calling string value converted to upper case.

Syntax

str.toUpperCase()

Return value

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

Description

The toUpperCase() method returns the value of the string converted to upper case. toUpperCase() does not affect the value of the string itself.

Examples

Using toUpperCase()

console.log('alphabet'.toUpperCase()); // '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.toUpperCase' in that specification.
Standard  
ECMAScript 2015 (6th Edition, ECMA-262)
The definition of 'String.prototype.toUpperCase' in that specification.
Standard  
ECMAScript 2017 Draft (ECMA-262)
The definition of 'String.prototype.toUpperCase' 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, ziyunfei, evilpie, Brettz9, Mgjbot, Ptak82, Maian, Dria
 Last updated by: eduardoboucas,