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The Object.entries() method returns an array of a given object's own enumerable property [key, value] pairs, in the same order as that provided by a loop (the difference being that a for-in loop enumerates properties in the prototype chain as well).




The object whose enumerable own property [key, value] pairs are to be returned.

Return value

An array of the given object's own enumerable property [key, value] pairs.


Object.entries() returns an array whose elements are arrays corresponding to the enumerable property [key, value] pairs found directly upon object. The ordering of the properties is the same as that given by looping over the property values of the object manually.


const obj = { foo: 'bar', baz: 42 };
console.log(Object.entries(obj)); // [ ['foo', 'bar'], ['baz', 42] ]

// array like object
const obj = { 0: 'a', 1: 'b', 2: 'c' };
console.log(Object.entries(obj)); // [ ['0', 'a'], ['1', 'b'], ['2', 'c'] ]

// array like object with random key ordering
const anObj = { 100: 'a', 2: 'b', 7: 'c' };
console.log(Object.entries(anObj)); // [ ['2', 'b'], ['7', 'c'], ['100', 'a'] ]

// getFoo is property which isn't enumerable
const myObj = Object.create({}, { getFoo: { value() { return; } } }); = 'bar';
console.log(Object.entries(myObj)); // [ ['foo', 'bar'] ]

// non-object argument will be coerced to an object
console.log(Object.entries('foo')); // [ ['0', 'f'], ['1', 'o'], ['2', 'o'] ]

// returns an empty array for any primitive type, since primitives have no own properties
console.log(Object.entries(100)); // [ ]

// iterate through key-value gracefully
const obj = { a: 5, b: 7, c: 9 };
for (const [key, value] of Object.entries(obj)) {
  console.log(`${key} ${value}`); // "a 5", "b 7", "c 9"

// Or, using array extras
Object.entries(obj).forEach(([key, value]) => {
console.log(`${key} ${value}`); // "a 5", "b 7", "c 9"

Converting an Object to a Map

The new Map() constructor accepts an iterable of entries. With Object.entries, you can easily convert from Object to Map:

const obj = { foo: 'bar', baz: 42 }; 
const map = new Map(Object.entries(obj));
console.log(map); // Map { foo: "bar", baz: 42 }

Iterating through an Object

Using Array Destructuring, you can iterate through objects easily.

const obj = { foo: 'bar', baz: 42 };
Object.entries(obj).forEach(([key, value]) => console.log(`${key}: ${value}`)); // "foo: bar", "baz: 42"


To add compatible Object.entries support in older environments that do not natively support it, you can find a demonstrational implementation of Object.entries in the tc39/proposal-object-values-entries (if you don't need any support for IE), a polyfill in the es-shims/Object.entries repositories, or you can use the simple, ready to deploy polyfill listed below. 

if (!Object.entries)
  Object.entries = function( obj ){
    var ownProps = Object.keys( obj ),
        i = ownProps.length,
        resArray = new Array(i); // preallocate the Array
    while (i--)
      resArray[i] = [ownProps[i], obj[ownProps[i]]];
    return resArray;

For the above polyfill code snippet, if you need support for IE < 9, then you will also need an Object.keys polyfill (such as the one found on the Object.keys page).


Specification Status Comment
ECMAScript Latest Draft (ECMA-262)
The definition of 'Object.entries' in that specification.
Draft Initial definition.
ECMAScript 2017 (ECMA-262)
The definition of 'Object.entries' in that specification.

Browser compatibility

FeatureChromeEdgeFirefoxInternet ExplorerOperaSafari
Basic support541447 No4110.1
FeatureAndroid webviewChrome for AndroidEdge mobileFirefox for AndroidOpera AndroidiOS SafariSamsung Internet
Basic support5454 Yes4741 No6.0

1. From version 6.5.0: this feature is behind the --harmony runtime flag.

See also