Run results for: for..of vs for simple vs for..in - MeasureThat.net

Run details:

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/94.0.4606.71 Safari/537.36

Browser: Chrome 94

Operating system: Linux

Device Platform: Desktop

Date tested: 3 years ago

Test name	Executions per second
for..of	3579747.5 Ops/sec
for..in	256972.9 Ops/sec
for	201042.4 Ops/sec
foreach	3472282.8 Ops/sec

Script Preparation code:

var arr = [12342, 342, 3423, 432, 432, 423, 43, 3, 1, 321, 323, 1, 31, 31, 31, 231, 31, 31];

Tests:

for..of
const narr = []; for(const item of arr){ narr.push(item) }
for..in
const narr = []; for(const item in arr){ narr.push(arr[item]) }
for
const narr = []; for(let i=0; i<arr.length; i++){ narr.push(arr[i]) }
foreach
const narr = []; arr.forEach( e => narr.push(e));