Run results for: className vs data attr querySelectorAll vs getElementsByClassName

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:128.0) Gecko/20100101 Firefox/128.0

Browser: Firefox 128

Operating system: Mac OS X 10.15

Device Platform: Desktop

Date tested: one year ago

Test name	Executions per second
querySelectorAll data attr	997866.6 Ops/sec
querySelectorAll data attr plus node name	835241.3 Ops/sec
querySelectorAll class name	1601445.1 Ops/sec
querySelectorAll class name plus node name	1247061.2 Ops/sec
querySelectorAll node name plus class name plus data attr	958688.8 Ops/sec
getElementsByClassName	13815789.0 Ops/sec

HTML Preparation code:

<div class="component-1" data-js="component-1"></div>
<div class="component-1" data-js="component-1"></div>
<div class="component-1" data-js="component-1"></div>
<div class="component-1" data-js="component-1"></div>
<div class="component-1" data-js="component-1"></div>
<div class="component-1" data-js="component-1"></div>
<div class="component-1" data-js="component-1"></div>
<div class="component-1" data-js="component-1"></div>
<div class="component-1" data-js="component-1"></div>
<div class="component-1" data-js="component-1"></div>
<div class="component-1" data-js="component-1"></div>
<div class="component-1" data-js="component-1"></div>
<div class="component-1" data-js="component-1"></div>
<div class="component-1" data-js="component-1"></div>
<div class="component-1" data-js="component-1"></div>
<div class="component-1" data-js="component-1"></div>
<div class="component-1" data-js="component-1"></div>
<div class="component-1" data-js="component-1"></div>
<div class="component-1" data-js="component-1"></div>
<div class="component-1" data-js="component-1"></div>
<div class="component-1" data-js="component-1"></div>
<div class="component-1" data-js="component-1"></div>
<div class="component-1" data-js="component-1"></div>
<div class="component-1" data-js="component-1"></div>

<div class="component-2" data-js="component-2"></div>
<div class="component-2" data-js="component-2"></div>
<div class="component-2" data-js="component-2"></div>
<div class="component-2" data-js="component-2"></div>
<div class="component-2" data-js="component-2"></div>
<div class="component-2" data-js="component-2"></div>
<div class="component-2" data-js="component-2"></div>
<div class="component-2" data-js="component-2"></div>
<div class="component-2" data-js="component-2"></div>
<div class="component-2" data-js="component-2"></div>
<div class="component-2" data-js="component-2"></div>
<div class="component-2" data-js="component-2"></div>
<div class="component-2" data-js="component-2"></div>
<div class="component-2" data-js="component-2"></div>
<div class="component-2" data-js="component-2"></div>
<div class="component-2" data-js="component-2"></div>
<div class="component-2" data-js="component-2"></div>
<div class="component-2" data-js="component-2"></div>
<div class="component-2" data-js="component-2"></div>
<div class="component-2" data-js="component-2"></div>
<div class="component-2" data-js="component-2"></div>
<div class="component-2" data-js="component-2"></div>
<div class="component-2" data-js="component-2"></div>
<div class="component-2" data-js="component-2"></div>

Tests:

querySelectorAll data attr
var result = document.querySelectorAll("[data-js='component-1']");
querySelectorAll data attr plus node name
var result = document.querySelectorAll("div[data-js='component-1']");
querySelectorAll class name
var result = document.querySelectorAll('.component-1')
querySelectorAll class name plus node name
var result = document.querySelectorAll('div.component-1');
querySelectorAll node name plus class name plus data attr
var result = document.querySelectorAll("div.component-1[data-js='component-1']");
getElementsByClassName
document.getElementsByClassName('component-1')

Run results for: className vs data attr querySelectorAll vs getElementsByClassName

This benchmark compares the performance of different methods for selecting elements in JavaScript: querySelectorAll and getElementsByClassName.

querySelectorAll data attr

querySelectorAll data attr plus node name

querySelectorAll class name

querySelectorAll class name plus node name

querySelectorAll node name plus class name plus data attr

getElementsByClassName