Run results for: JavaScript spread operator vs Object.assign performance to merge into new object

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/119.0.0.0 Safari/537.36

Browser: Chrome 119

Operating system: Mac OS X 10.15.7

Device Platform: Desktop

Date tested: 2 years ago

Using the spread operator

42.9M/s

Using Object.assign

10.8M/s

View exact numbers

Test name	Executions per second
✓ Using the spread operator	42,891,840 Ops/sec
Using Object.assign	10,813,126 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);