Run results for: for vs for...in vs forEach

Run details:

User agent: Mozilla/5.0 (Linux; Android 8.1.0; MI PAD 4) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.136 Safari/537.36

Browser: Chrome 74

Operating system: Android 8.1.0

Device Platform: Desktop

Date tested: 5 years ago

Script Preparation code:

arr = [];
arr.length = 800000;
arr.fill(0)

AخA
 
arr = [];arr.length = 800000;arr.fill(0)

Tests:

let sum = 0;
for (let i = 0; i < arr.length; i++) {
  sum += arr[i];
}

 
let sum = 0;for (let i = 0; i < arr.length; i++) {  sum += arr[i];}

forEach
let sum = 0; arr.forEach(value => sum += value);
let sum = 0;
arr.forEach(value => sum += value);

let sum = 0;
for (let i in arr) {
  sum += i;
}

 
let sum = 0;for (let i in arr) {  sum += i;}