Run results for: Object iteration for-in vs object.keys

Run details:

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: Chrome 135

Operating system: Windows

Device Platform: Desktop

Date tested: one year ago

Object.keys

41/s

for-in

40/s

View exact numbers

Test name	Executions per second
✓ Object.keys	41 Ops/sec
for-in	40 Ops/sec

Script Preparation code:

var obj = {};
for (var i = 10000; i > 0; i--) {
    obj[`key ${i}`] = i;
}

Tests: