Symbol.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 September 2015.

The valueOf() method of Symbol values returns this symbol value.

Try it

const symbol1 = Symbol("foo");

console.log(typeof Object(symbol1));
// Expected output: "object"

console.log(typeof Object(symbol1).valueOf());
// Expected output: "symbol"

Syntax

js
valueOf()

Parameters

None.

Return value

The primitive value of the specified Symbol object.

Description

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

JavaScript calls the valueOf() method to convert an object to a primitive value. You rarely need to invoke the valueOf() method yourself; JavaScript automatically invokes it when encountering an object where a primitive value is expected.

Examples

Using valueOf()

js
const sym = Symbol("example");
sym === sym.valueOf(); // true

Specifications

Specification
ECMAScript® 2025 Language Specification
# sec-symbol.prototype.valueof

Browser compatibility

Report problems with this compatibility data on GitHub
desktopmobileserver
Chrome
Edge
Firefox
Opera
Safari
Chrome Android
Firefox for Android
Opera Android
Safari on iOS
Samsung Internet
WebView Android
WebView on iOS
Deno
Node.js
valueOf

Legend

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Full support
Full support

See also