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

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/79.0.3945.130 Safari/537.36

Browser: Chrome 79

Operating system: Windows

Device Platform: Desktop

Date tested: 4 years ago

Test name	Executions per second
Object.entries	25066.3 Ops/sec
Object.keys	51982.8 Ops/sec
Object.keys with extra array	32851.5 Ops/sec
Object.entries without array	26144.5 Ops/sec
Object for..in	202965.4 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 = {}; Object.entries(window.parentObj).forEach(([k, v], i) => { if ((i % 2) === 0) { newObj[k] = v; } });
Object.keys
const newObj = {}; Object.keys(window.parentObj).forEach((k, i) => { if ((i % 2) === 0) { newObj[k] = window.parentObj[k]; } });
Object.keys with extra array
const newObj = {}; Object.keys(window.parentObj).forEach((k, i) => { const [extraK, v] = [k, window.parentObj[k]] if ((i % 2) === 0) { newObj[extraK] = v; } });
Object.entries without array
const newObj = {}; Object.entries(window.parentObj).forEach((keyAndVal, i) => { if ((i % 2) === 0) { newObj[keyAndVal[0]] = keyAndVal[1]; } });
Object for..in
const newObj = {}; for(var key in window.parentObj) { if ((i % 2) === 0) { newObj[key] = window.parentObj[key] } };

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

Object.entries

Object.keys

Object.keys with extra array

Object.entries without array

Object for..in