🔁JS array looping

There are a few different ways to loop over an array:

for

for (var i = 0; i < array.length; i++) {
  array[i]
}

forEach

array.forEach(function (i) {
  array[i]
})

for in

for (var i in array) {
  array[i]
}

for..of

for (var i of array) {
  array[i]
}

Test results

Test case nameResult
forfor x 4,680,671 ops/sec ±0.42% (68 runs sampled)
forEachforEach x 5,043,765 ops/sec ±0.60% (67 runs sampled)
for infor in x 9,155,750 ops/sec ±0.50% (68 runs sampled)
for..offor..of x 1,339,234 ops/sec ±0.42% (68 runs sampled)

for...of uses @iterators internally which aren’t as efficient