Run results for: querySelectorAll vs getElementsByTagName iteration

Run details:

User agent: Mozilla/5.0 (X11; Linux x86_64; rv:81.0) Gecko/20100101 Firefox/81.0

Browser: Firefox 81

Operating system: Linux

Device Platform: Desktop

Date tested: 3 years ago

Test name	Executions per second
querySelectorAll	281242.3 Ops/sec
getElementsByTagName	316276.7 Ops/sec

HTML Preparation code:

<div></div>
<div></div>
<div></div>
<div></div>
<div></div>
<div></div>
<div></div>
<div></div>
<div></div>
<div></div>

Tests:

querySelectorAll
const allDivs = document.querySelectorAll('div'); allDivs.forEach(function (div) {});
getElementsByTagName
const allDivs = document.getElementsByTagName('div'); const arrayAllDivs = Array.from(allDivs); arrayAllDivs.forEach(function (div) {});