Run results for: Performance of JavaScript .reduce vs. for vs. for..of

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/135.0.0.0 Safari/537.36

Browser: Chrome 135

Operating system: Mac OS X 10.15.7

Device Platform: Desktop

Date tested: one year ago

for

183.4M/s

for..of (reduce)

180.4M/s

.reduce (destructuring)

62.0M/s

for..of (reduce) (destructuring)

60.7M/s

.reduce

53.4M/s

View exact numbers

Script Preparation code:

const array = [];
for (let i = 0; i < 1000000; ++i) {
    result.push({
        a: i,
        b: i / 2,
    });
}

Tests:

for
const r = 0; for (let i = 0; i < array.length; ++i) { r += array[i].a + array[i].b; }
.reduce
array.reduce((p, x) => p + x.a + x.b, 0);
.reduce (destructuring)
array.reduce((p, {a,b}) => p + a + b, 0);
for..of (reduce)
let r = 0; for (const x of array) { r += x.a + x.b; }
for..of (reduce) (destructuring)
let r = 0; for (const {a,b} of array) { r += a + b; }