Run results for: flatMap() vs filter().map() vs reduce() vs forOf loop v8

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/138.0.0.0 Safari/537.36 Edg/138.0.0.0

Browser: Chrome 138

Operating system: Windows

Device Platform: Desktop

Date tested: one year ago

filter().map()

12K/s

reduce()

10K/s

flatMap()

7K/s

forof loop

828/s

View exact numbers

Script Preparation code:

var arr = [];
var i = 0;

while (i <= 10000) arr[i] = i++;

Tests:

filter().map()
arr.filter(x => x % 2).map(x => x/100)
flatMap()
arr.flatMap(x => x % 2 ? x/100 : [])
reduce()
arr.reduce((newArray, x) => { if (x % 2) { newArray.push(x / 100) } return newArray }, [])
forof loop
newArray = []; for (x of arr){ if (x % 2) { newArray.push(x / 100) } }