String.prototype.valueOf()

Baseline Widely available

This feature is well established and works across many devices and browser versions. Its been available across browsers since July 2015.

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The valueOf() method of String values returns this string value.

Try it

const stringObj = new String("foo");

console.log(stringObj);
// Expected output: String { "foo" }

console.log(stringObj.valueOf());
// Expected output: "foo"

Syntax

valueOf()

Parameters

None.

Return value

A string representing the primitive value of a given String object.

Description

The valueOf() method of String returns the primitive value of a String object as a string data type. This value is equivalent to String.prototype.toString().

This method is usually called internally by JavaScript and not explicitly in code.

Examples

Using `valueOf()`

const x = new String("Hello world");
console.log(x.valueOf()); // 'Hello world'

Specifications

Specification
ECMAScript 2027 LanguageSpecification # sec-string.prototype.valueof

Browser compatibility

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Standard built-in objects
String
Constructor
1. String()
Static methods
Instance methods
Instance properties
1. length
Inheritance
Object/Function
Static methods
Static properties
Instance methods
Instance properties
1. __proto__
2. constructor