Run results for: getElementById vs QuerySelector nested element

Run details:

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/125.0.0.0 Safari/537.36

Browser: Chrome 125

Operating system: Linux

Device Platform: Desktop

Date tested: one year ago

Test name	Executions per second
getElementById + firstElementChild	8508166.0 Ops/sec
querySelector	4458360.0 Ops/sec

HTML Preparation code:


<div id="testElmt">
  <p>paragraph</p>
</div>

Tests:

getElementById + firstElementChild
const par = document.getElementById("testElmt").firstElementChild;
querySelector
const par = document.querySelector("#testElmt p");