Benchmark: JavaScript spread operator vs Object.assign from empty object performance

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);

Rendered benchmark preparation results:

Previous results

Test case name	Result
Using the spread operator
Using Object.assign

Latest run results:

Run details: (Test run date: one year ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/135.0.0.0 Safari/537.36

Browser/OS: Chrome 135 on Windows

Using the spread operator

34.9M/s

Using Object.assign

25.9M/s

View exact numbers

Test name	Executions per second
✓ Using the spread operator	34,911,964 Ops/sec
Using Object.assign	25,909,728 Ops/sec

JavaScript spread operator vs Object.assign from empty object performance (version: 1)