Run results for: JavaScript spread operator vs object update vs object assign performance

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/18.1.1 Safari/605.1.15

Browser: Safari 18

Operating system: Mac OS X 10.15.7

Device Platform: Desktop

Date tested: 9 months ago

Using update

627.7M/s

Using Object.assign

42.8M/s

Using spread

32.7M/s

View exact numbers

Tests:

Using update
const firstObject = {} firstObject.sampleData = 'Hello world'; firstObject.moreData = 'foo bar';
Using Object.assign
const firstObject = { sampleData: 'Hello world' } const secondObject = { moreData: 'foo bar' } const finalObject = Object.assign(firstObject, secondObject);
Using spread
const firstObject = { sampleData: 'Hello world' } const secondObject = { moreData: 'foo bar' } const finalObject = {...firstObject, ...secondObject }