JavaScript Object.keys()

Use Object.keys() on an array:

const fruits = ["Banana", "Orange", "Apple", "Mango"];
const keys = Object.keys(fruits);

Use Object.keys() on a string:

const fruits = "Banana";
const keys = Object.keys(fruits);

Use Object.keys() on an object:

const person = {
  firstName: "John",
  lastName: "Doe",
  age: 50,
  eyeColor: "blue"
};
const keys = Object.keys(person);

Description

The Object.keys() method returns an Array Iterator object with the keys of an object.

The Object.keys() method does not change the original object.

Object.keys(object)

Parameter	Description
object	Required. An iterable object.

Type	Description
An array	An Array Iterator object containing the keys of an object.

Object.keys() is an ECMAScript6 (ES6) feature.

ES6 (JavaScript 2015) is supported in all modern browsers since June 2017:


Chrome 51	Edge 15	Firefox 54	Safari 10	Opera 38
May 2016	Apr 2017	Jun 2017	Sep 2016	Jun 2016

Object.keys() is not supported in Internet Explorer.