Run results for: JavaScript spread operator vs Object.fromentries performance

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/137.0.0.0 Safari/537.36

Browser: Chrome 137

Operating system: Mac OS X 10.15.7

Device Platform: Desktop

Date tested: one year ago

Benchmark engine: Benchmark.js

Using the spread operator

53.3M/s

Using Object.assign

6.0M/s

View exact numbers

Test name	Executions per second
✓ Using the spread operator	53,266,676 Ops/sec
Using Object.assign	5,968,606 Ops/sec

Tests:

Using the spread operator
const firstObject = { sampleData: 'Hello world' } const secondObject = { moreData: 'foo bar' } const finalObject = { ...firstObject, ...secondObject };
Using Object.assign
const firstObject = { sampleData: 'Hello world' } const secondObject = { moreData: 'foo bar' } const a1 = Object.entries(firstObject) const a2 = Object.entries(secondObject) const finalObject = Object.fromEntries(a1.concat(a2));