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Boolean.prototype.valueOf() - JavaScript | MDN
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Using
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
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