Run results for: indexOf vs map vs Set vs native Map

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/131.0.0.0 Safari/537.36

Browser: Chrome 131

Operating system: Windows

Device Platform: Desktop

Date tested: one year ago

Benchmark engine: Benchmark.js

map2

10.1M/s

set

9.7M/s

map

8.6M/s

indexOf

3K/s

View exact numbers

Test name	Executions per second
✓ map2	10,097,610 Ops/sec
set	9,664,027 Ops/sec
map	8,589,416 Ops/sec
indexOf	2,914 Ops/sec

Script Preparation code:

var array = [];
for (var i=0; i<3000; ++i) {
  	array.push('00' + i);
}

function hasWithIndexOf(needle) {
	return array.indexOf(needle) !== -1;
}

var map = {};
array.forEach(item => map[item] = true);

function hasWithMap(needle) {
	return needle in map;
}

var set = new Set(array);

function hasWithSet(needle) {
	return set.has(needle);
}

var map2 = new Map(array.map(item => [item, true]));

function hasWithMap2(needle) {
	return map2.has(needle);
}

Tests:

indexOf
for (var i=0; i<100; ++i) { hasWithIndexOf('404'); }
map
for (var i=0; i<100; ++i) { hasWithMap('404'); }
set
for (var i=0; i<100; ++i) { hasWithSet('404'); }
map2
for (var i=0; i<100; ++i) { hasWithMap2('404'); }