Run results for: getElementById vs querySelector

Run details:

User agent: Mozilla/5.0 (iPhone; CPU iPhone OS 10_3_3 like Mac OS X) AppleWebKit/603.1.30 (KHTML, like Gecko) CriOS/71.0.3578.89 Mobile/14G60 Safari/602.1

Browser: Chrome Mobile iOS 71

Operating system: iOS 10.3.3

Device Platform: Mobile

Date tested: 4 years ago

Test name	Executions per second
getElementById	1939184.0 Ops/sec
querySelector	1563043.0 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;