Run results for: Javascript: reduce VS for

Compare the "reduce" method with the "for" iteration method. Use case: There is an array with different numbers, we will compare the performance between the two methods to find the quantity of numbers greater than zero in the array list.

Run details:

User agent: Mozilla/5.0 (Linux; arm_64; Android 11; Redmi Note 9S) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/132.0.6834.2144 YaApp_Android/25.20.1 YaSearchBrowser/25.20.1 BroPP/1.0 SA/3 Mobile Safari/537.36

Browser: Chrome 132

Operating system: Android 25.20.1

Device Platform: Mobile

Date tested: one year ago

Number 2: using reduce method

22.0M/s

Number 1: use for iterator

10.2M/s

View exact numbers

Test name	Executions per second
✓ Number 2: using reduce method	22,009,280 Ops/sec
Number 1: use for iterator	10,151,324 Ops/sec

Script Preparation code:

var list = [1, 0, -2, -1, 3, 0, 1, 8, -10, 3, 0, -1, -3];

Tests:

Number 1: use for iterator
let countNumberGreaterThanZero = 0; for (let i = 0; i < list.length; i++) { if (list[i] > 0) { countNumberGreaterThanZero++; } }
Number 2: using reduce method
let countsNumbersGreaterThanZero = (acc, cur) => acc + (cur > 0 ? 1 : 0); list.reduce(countsNumbersGreaterThanZero, 0)