Run results for: getElementById vs querySelector, with ten elements

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:122.0) Gecko/20100101 Firefox/122.0

Browser: Firefox 122

Operating system: Windows

Device Platform: Desktop

Date tested: 2 years ago

Test name	Executions per second
getElementById	7635707.5 Ops/sec
querySelector	3896872.2 Ops/sec

HTML Preparation code:

<div id="testElement1"></div>
<div id="testElement2"></div>
<div id="testElement3"></div>
<div id="testElement4"></div>
<div id="testElement5"></div>
<div id="testElement6"></div>
<div id="testElement7"></div>
<div id="testElement8"></div>
<div id="testElement9"></div>
<div id="testElement10"></div>

Tests:

getElementById
var el = document.getElementById('testElement1'); var className = el.className;
querySelector
var el = document.querySelector('#testElement1'); var className = el.className;