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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) |