Run results for: Object.fromEntries vs reduce vs Map vs for of vs forEach

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/121.0.0.0 Safari/537.36

Browser: Chrome 121

Operating system: Windows

Device Platform: Desktop

Date tested: 2 years ago

for...of

5K/s

forEach

5K/s

Reduce (reuse object)

4K/s

Map

2K/s

Object.fromEntries

304/s

View exact numbers

Script Preparation code:

var data = { ...Array.from(Array(10000).keys()) };

Tests:

Object.fromEntries
Object.fromEntries(Object.entries(data).map((key, value) => [key, value]));
Reduce (reuse object)
Object.entries(data).reduce((acc, [k, v]) => { acc[k] = v.toString(); return acc; }, {});
for...of
const result = {}; for (const [key, value] of Object.entries(data)) { result[key] = value; } return result;
Map
Object.entries(data).reduce((acc, [k, v]) => { acc.set(k, v.toString()) return acc; }, new Map());
forEach
const result = {}; Object.entries(data).forEach(entry => { const [key, value] = entry; result[key] = value; }); return result;