Run results for: getElementById vs querySelector

Run details:

User agent: Mozilla/5.0 (Linux; Android 8.0.0; Mi MIX 2 Build/OPR1.170623.027) AppleWebKit/537.36 (KHTML, like Gecko) SamsungBrowser/7.4 Chrome/59.0.3071.125 Mobile Safari/537.36

Browser: Chrome Mobile 59

Operating system: Android 8.0.0

Device Platform: Mobile

Date tested: 6 years ago

Test name	Executions per second
getElementById	738835.7 Ops/sec
querySelector	363016.8 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;