Run results for: Map vs Object access and check

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:73.0) Gecko/20100101 Firefox/73.0

Browser: Firefox 73

Operating system: Windows

Device Platform: Desktop

Date tested: 4 years ago

Test name	Executions per second
Map lookup	2533.8 Ops/sec
Obj lookup	8225.3 Ops/sec

Script Preparation code:

var map = new Map();
var obj = {};

map.set('a', 5);
obj['a'] = 5;

var i = 0, count = 1000, a;

Tests:

Map lookup
for (i = 0; i < count; i++) { a = map.get('a'); const exists = map.has('a') }
Obj lookup
for (i = 0; i < count; i++) { a = obj['a']; const exists = 'a' in obj; }