Run results for: getElementById vs querySelector

Run details:

User agent: Mozilla/5.0 (Linux; U; Android 6.0.1; en-us; Redmi 4 Build/MMB29M) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/79.0.3945.147 Mobile Safari/537.36 XiaoMi/MiuiBrowser/12.10.5-go

Browser: Chrome Mobile 79

Operating system: Android 6.0.1

Device Platform: Mobile

Date tested: 3 years ago

Test name	Executions per second
getElementById	591322.2 Ops/sec
querySelector	263388.3 Ops/sec

HTML Preparation code:

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

AخA
 
<div id="testElement"></div>

Tests:

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