Run results for: Object.fromEntries vs reduce vs For-Each

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/133.0.0.0 Safari/537.36

Browser: Chrome 133

Operating system: Mac OS X 10.15.7

Device Platform: Desktop

Date tested: one year ago

Reduce (reuse object)

3K/s

Object.fromEntries

341/s

For-each

328/s

Reduce (creating temporary objects)

93/s

View exact numbers

Test name	Executions per second
✓ Reduce (reuse object)	2,960 Ops/sec
Object.fromEntries	341 Ops/sec
For-each	328 Ops/sec
Reduce (creating temporary objects)	93 Ops/sec

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; }, {});
Reduce (creating temporary objects)
Object.entries(data).reduce((acc, [k, v]) => ({ ...acc, [k]: v.toString() }), {});
For-each
const res = {}; Object.entries(data).forEach((key, value) => { res[key] = value; });