Run results for: getElementById vs querySelector

Run details:

User agent: Mozilla/5.0 (iPhone; CPU iPhone OS 16_2 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/16.2 Mobile/15E148 Safari/604.1

Browser: Mobile Safari 16

Operating system: iOS 16.2

Device Platform: Mobile

Date tested: 2 years ago

getElementById

11.7M/s

querySelector

7.0M/s

View exact numbers

Test name	Executions per second
✓ getElementById	11,671,553 Ops/sec
querySelector	7,006,777 Ops/sec

HTML Preparation code:

<div id="testElement"></div>

Tests:

getElementById
var el = document.getElementById('testElement'); var className = el.className;
querySelector
var el = document.querySelector('#testElement'); var className = el.className;