Run results for: checks if object has any key - Object.keys vs for key in 2

Run details:

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/132.0.0.0 Safari/537.36

Browser: Chrome 132

Operating system: Linux

Device Platform: Desktop

Date tested: one year ago

for key .. in

144.8M/s

Object.keys

109.5M/s

View exact numbers

Test name	Executions per second
✓ for key .. in	144,770,944 Ops/sec
Object.keys	109,543,128 Ops/sec

Script Preparation code:

var obj = {}
new Array(1000).map((item, index) => {
    obj[index] = index
})

Tests: