Web/JavaScript/Reference/Global objects/Object/getOwnPropertyDescriptor

The Object.getOwnPropertyDescriptor() method returns an object describing the configuration of a specific property on a given object (that is, one directly present on an object and not in the object's prototype chain). The object returned is mutable but mutating it has no effect on the original property's configuration.

The source for this interactive example is stored in a GitHub repository. If you'd like to contribute to the interactive examples project, please clone https://github.com/mdn/interactive-examples and send us a pull request.

Syntax

Object.getOwnPropertyDescriptor(obj, prop)

Parameters

obj: The object in which to look for the property.
prop: The name or Symbol of the property whose description is to be retrieved.

Return value

A property descriptor of the given property if it exists on the object, undefined otherwise.

Description

This method permits examination of the precise description of a property. A property in JavaScript consists of either a string-valued name or a Symbol and a property descriptor. Further information about property descriptor types and their attributes can be found in Object.defineProperty().

A property descriptor is a record with some of the following attributes:

value: The value associated with the property (data descriptors only).
writable: true if and only if the value associated with the property may be changed (data descriptors only).
get: A function which serves as a getter for the property, or undefined if there is no getter (accessor descriptors only).
set: A function which serves as a setter for the property, or undefined if there is no setter (accessor descriptors only).
configurable: true if and only if the type of this property descriptor may be changed and if the property may be deleted from the corresponding object.
enumerable: true if and only if this property shows up during enumeration of the properties on the corresponding object.

Examples

Using Object.getOwnPropertyDescriptor

var o, d;

o = { get foo() { return 17; } };
d = Object.getOwnPropertyDescriptor(o, 'foo');
// d is {
//   configurable: true,
//   enumerable: true,
//   get: /*the getter function*/,
//   set: undefined
// }

o = { bar: 42 };
d = Object.getOwnPropertyDescriptor(o, 'bar');
// d is {
//   configurable: true,
//   enumerable: true,
//   value: 42,
//   writable: true
// }

o = { [Symbol.for('baz')]: 73 }
d = Object.getOwnPropertyDescriptor(o, Symbol.for('baz')); 
// d is {
//   configurable: true,
//   enumerable: true,
//   value: 73,
//   writable: true
// }

o = {};
Object.defineProperty(o, 'qux', {
  value: 8675309,
  writable: false,
  enumerable: false
});
d = Object.getOwnPropertyDescriptor(o, 'qux');
// d is {
//   value: 8675309,
//   writable: false,
//   enumerable: false,
//   configurable: false
// }

Non-object coercion

In ES5, if the first argument to this method is not an object (a primitive), then it will cause a TypeError. In ES2015, a non-object first argument will be coerced to an object at first.

Object.getOwnPropertyDescriptor('foo', 0);
// TypeError: "foo" is not an object  // ES5 code

Object.getOwnPropertyDescriptor('foo', 0);
// Object returned by ES2015 code: {
//   configurable: false,
//   enumerable: true,
//   value: "f",
//   writable: false
// }

Specifications

Specification
ECMAScript (ECMA-262)The definition of 'Object.getOwnPropertyDescriptor' in that specification.

Browser compatibility

Update compatibility data on GitHub

	Desktop						Mobile						Server
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet	Node.js
`getOwnPropertyDescriptor`	Chrome Full support 5	Edge Full support 12	Firefox Full support 4	IE Full support 9 Full support 9 Partial support 8 Notes' Notes' In Internet Explorer 8, this was only supported on DOM objects and with some non-standard behaviors. This was later fixed in Internet Explorer 9.	Opera Full support 12	Safari Full support 5	WebView Android Full support 1	Chrome Android Full support 18	Firefox Android Full support 4	Opera Android Full support 12	Safari iOS Full support 5	Samsung Internet Android Full support 1.0	nodejs Full support Yes

Legend

Full support: Full support
See implementation notes.': See implementation notes.