Run results for: Object.entries VS Object.keys VS Object.keys with extra array VS Object.entries without array 103

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:128.0) Gecko/20100101 Firefox/128.0

Browser: Firefox 128

Operating system: Windows

Device Platform: Desktop

Date tested: 2 years ago

For in

1.4M/s

For of keys

835K/s

Object.keys

821K/s

Object.entries without array

513K/s

Object.entries

487K/s

For of entries

440K/s

View exact numbers

Test name	Executions per second
✓ For in	1,445,940 Ops/sec
For of keys	834,820 Ops/sec
Object.keys	820,517 Ops/sec
Object.entries without array	512,904 Ops/sec
Object.entries	487,343 Ops/sec
For of entries	439,762 Ops/sec

Script Preparation code:

function makeid() {
  var text = "";
  var possible = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789";

  for (var i = 0; i < 5; i++)
    text += possible.charAt(Math.floor(Math.random() * possible.length));

  return text;
}

window.parentObj = {};

for (let i = 0; i < 100; i++) {
	window.parentObj[makeid()] = makeid();
}

Tests:

Object.entries
const newObj = {}; const parentObj = window.parentObj; Object.entries(parentObj).forEach(([k, v], i) => { newObj[k] = v; });
Object.keys
const newObj = {}; const parentObj = window.parentObj; Object.keys(parentObj).forEach((k, i) => { newObj[k] = parentObj[k]; });
Object.entries without array
const newObj = {}; Object.entries(window.parentObj).forEach((keyAndVal, i) => { newObj[keyAndVal[0]] = keyAndVal[1]; });
For in
const newObj = {}; const parentObj = window.parentObj; for (let key in parentObj) { newObj[key] = parentObj[key]; }
For of keys
const newObj = {}; const parentObj = window.parentObj; for (let key of Object.keys(parentObj)) { newObj[key] = parentObj[key]; }
For of entries
const newObj = {}; const parentObj = window.parentObj; for (let kv of Object.entries(parentObj)) { newObj[kv[0]] = kv[1]; }