Run results for: JavaScript spread operator vs Object.assign performance (single addition)

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/139.0.0.0 Safari/537.36 Edg/139.0.0.0

Browser: Chrome 139

Operating system: Windows

Device Platform: Desktop

Date tested: 11 months ago

Using the spread operator

34.5M/s

Using Object.assign

17.6M/s

View exact numbers

Test name	Executions per second
✓ Using the spread operator	34,520,148 Ops/sec
Using Object.assign	17,588,688 Ops/sec

Tests:

Using the spread operator
const obj = { sampleData: 'Hello world' } const finalObj = { ...obj, single: 'foo' };
Using Object.assign
const obj = { sampleData: 'Hello world' } const finalObj = Object.assign(obj, { single: 'foo' });