Run results for: getElementById vs querySelector

Run details:

User agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:91.0) Gecko/20100101 Firefox/91.0

Browser: Firefox 91

Operating system: Ubuntu

Device Platform: Desktop

Date tested: 2 years ago

Test name	Executions per second
getElementById	4556747.0 Ops/sec
querySelector	3116383.0 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;