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

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_3) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/114.0.0.0 YaBrowser/23.7.0.2610 Yowser/2.5 Safari/537.36

Browser: Yandex Browser 23

Operating system: Mac OS X 10.14.3

Device Platform: Desktop

Date tested: 2 years ago

Using Object.assign

3.3M/s

Using the spread operator

1.3M/s

View exact numbers

Test name	Executions per second
✓ Using Object.assign	3,343,197 Ops/sec
Using the spread operator	1,307,374 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 finalObject = Object.assign(firstObject, secondObject);