Run results for: Map vs Object read performance for a 1000 key lookup

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

Obj lookup

8K/s

Map lookup

6K/s

obj insert

129/s

map-insert

66/s

View exact numbers

Script Preparation code:

var map = new Map();
var obj = {};

map.set('a', 5);
obj['a'] = 5;

var numberOfEntries = 100000

  

let i = 0;
var count = 1000;
var a;

Tests:

map-insert
for (let j = 0; j < numberOfEntries; j++){ const key = `a-${j}`; const value = j; map.set(key,value) obj[key] = value; }
obj insert
for (let j = 0; j < numberOfEntries; j++){ const key = `a-${j}`; const value = j; obj[key] = value; }
Map lookup
for (i = 0; i < count; i++) { const key = `a-${i}`; a = map.get(key); }
Obj lookup
for (i = 0; i < count; i++) { const key = `a-${i}`; a = obj[key]; }