Run results for: Array foreach vs for..in

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/16.5 Safari/605.1.15

Browser: Safari 16

Operating system: Mac OS X 10.15.7

Device Platform: Desktop

Date tested: one year ago

foreach

982K/s

for in

121K/s

View exact numbers

Test name	Executions per second
✓ foreach	981,912 Ops/sec
for in	121,405 Ops/sec

Script Preparation code:

var array = [];
for(let i = 0; i <= 100; i++) {
  array[i] = i;
}

Tests:

for in
let sum = 0; for (var sample in array) { sum += Number(sample); } console.log(sum);
foreach
let sum = 0; array.forEach((sample) => { sum += sample; }); console.log(sum);