Boolean.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 Boolean values returns the primitive value of a Boolean object.

Try it

const x = new Boolean();

console.log(x.valueOf());
// Expected output: false

const y = new Boolean("Mozilla");

console.log(y.valueOf());
// Expected output: true

Syntax

valueOf()

Parameters

None.

Return value

The primitive value of the given Boolean object.

Description

The valueOf() method of Boolean returns the primitive value of a Boolean object or literal Boolean as a Boolean data type.

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

Examples

Using `valueOf()`

const x = new Boolean();
const myVar = x.valueOf(); // assigns false to myVar

Specifications

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

Browser compatibility

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