W3cubDocs

Reflect.getPrototypeOf()

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since ⁨September 2016⁩.

The Reflect.getPrototypeOf() static method is like Object.getPrototypeOf(). It returns the prototype of the specified object.

Try it

const object = {
  foo: 42,
};

const proto = Reflect.getPrototypeOf(object);

console.log(proto);
// Expected output: Object {  }

console.log(Reflect.getPrototypeOf(proto));
// Expected output: null

Syntax

Reflect.getPrototypeOf(target)

Parameters

target: The target object of which to get the prototype.

Return value

The prototype of the given object, which may be an object or null.

Exceptions

TypeError: Thrown if target is not an object.

Description

Reflect.getPrototypeOf() provides the reflective semantic of retrieving the prototype of an object. The only difference with Object.getPrototypeOf() is how non-object targets are handled. Reflect.getPrototypeOf() throws a TypeError if the target is not an object, while Object.getPrototypeOf() coerces it to an object.

Reflect.getPrototypeOf() invokes the [[GetPrototypeOf]] object internal method of target.

Examples

Using Reflect.getPrototypeOf()

Reflect.getPrototypeOf({}); // Object.prototype
Reflect.getPrototypeOf(Object.prototype); // null
Reflect.getPrototypeOf(Object.create(null)); // null

Difference with Object.getPrototypeOf()

// Same result for Objects
Object.getPrototypeOf({}); // Object.prototype
Reflect.getPrototypeOf({}); // Object.prototype

// Both throw in ES5 for non-Objects
Object.getPrototypeOf("foo"); // Throws TypeError
Reflect.getPrototypeOf("foo"); // Throws TypeError

// In ES2015 only Reflect throws, Object coerces non-Objects
Object.getPrototypeOf("foo"); // String.prototype
Reflect.getPrototypeOf("foo"); // Throws TypeError

// To mimic the Object ES2015 behavior you need to coerce
Reflect.getPrototypeOf(Object("foo")); // String.prototype

Specifications

Specification
ECMAScript® 2026 Language Specification> # sec-reflect.getprototypeof>

Browser compatibility

	Desktop					Mobile							Server
	Chrome	Edge	Firefox	Opera	Safari	Chrome Android	Firefox for Android	Opera Android	Safari on IOS	Samsung Internet	WebView Android	WebView on iOS	Bun	Deno	Node.js
`getPrototypeOf`	49	12	42	36	10	49	42	36	10	5.0	49	10	1.0.0	1.0	6.0.0