string.toUpperCase

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

See also

• String.prototype.toLocaleLowerCase()
• String.prototype.toLocaleUpperCase()
• String.prototype.toLowerCase()