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

Run details:

User agent: Mozilla/5.0 (X11; Linux x86_64; rv:131.0) Gecko/20100101 Firefox/131.0

Browser: Firefox 131

Operating system: Linux

Device Platform: Desktop

Date tested: one year ago

Using Object.assign

9.5M/s

Using the spread operator

5.5M/s

View exact numbers

Test name	Executions per second
✓ Using Object.assign	9,526,587 Ops/sec
Using the spread operator	5,488,100 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);