Run results for: indexOf vs map

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

Benchmark engine: Benchmark.js

map

10.0M/s

indexOf

39K/s

View exact numbers

Test name	Executions per second
✓ map	10,007,099 Ops/sec
indexOf	39,160 Ops/sec

Script Preparation code:

var array = [];
for (var i=0; i<300; ++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;
}

Tests:

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