Boolean.prototype.valueOf()

Baseline Widely available

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

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

js
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()

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

Specifications

Specification
ECMAScript® 2026 Language Specification
# sec-boolean.prototype.valueof

Browser compatibility

See also