Run results for: Object.keys vs for in loop

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:120.0) Gecko/20100101 Firefox/120.0

Browser: Firefox 120

Operating system: Mac OS X 10.15

Device Platform: Desktop

Date tested: one year ago

Test name	Executions per second
for in loop	37500.4 Ops/sec
Object.keys	67743.7 Ops/sec

Script Preparation code:

var data = {};
for (var i = 0; i < 10000; i++) {
  data[`a${i}`] = i;
}

Tests:

for in loop
let hasKey = false; for (let key in data) { if (key === 'a998') { hasKey = true; } }
Object.keys
const hasKey = Object.keys(data).includes('a998');