Run results for: Get elements by class: jQuery vs querySelectorAll vs getElementsByClassName (Jquery 3.3.1)

Run details:

User agent: Mozilla/5.0 (Linux; Android 10; 6201) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/91.0.4472.114 Mobile Safari/537.36 OPR/64.2.3282.60128

Browser: Opera Mobile 64

Operating system: Android

Device Platform: Mobile

Date tested: 2 years ago

Test name	Executions per second
jQuery	32441.8 Ops/sec
querySelectorAll	101026.6 Ops/sec
getElementsByClassName	441462.1 Ops/sec
jQuery: mixed selector	24694.3 Ops/sec
querySelectorAll: mixed selector	76593.3 Ops/sec

HTML Preparation code:

<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>

<ul id="theList">
  <li class="odd">Item 1</li>    
  <li class="even">Item 2</li>    
  <li class="odd">Item 3</li>    
  <li class="even">Item 4</li>    
  <li class="odd">Item 5</li>    
  <li class="even">Item 6</li>    
  <li class="odd">Item 7</li>    
  <li class="even">Item 8</li>    
  <li class="odd">Item 9</li>    
  <li class="even">Item 10</li>    
  <li class="odd">Item 11</li>    
  <li class="even">Item 12</li>    
  <li class="odd">Item 13</li>    
  <li class="even">Item 14</li>    
  <li class="odd">Item 15</li>    
  <li class="even">Item 16</li>    
  <li class="odd">Item 17</li>    
  <li class="even">Item 18</li>    
  <li class="odd">Item 19</li>    
  <li class="even">Item 20</li>    
  <li class="odd">Item 21</li>    
  <li class="even">Item 22</li>    
  <li class="odd">Item 23</li>    
  <li class="even">Item 24</li>    
  <li class="odd">Item 25</li>    
  <li class="even">Item 26</li>    
  <li class="odd">Item 27</li>    
  <li class="even">Item 28</li>    
  <li class="odd">Item 29</li>    
  <li class="even">Item 30</li>    
</ul>

Tests:

jQuery
var els = $('.even');
querySelectorAll
var els = document.querySelectorAll('.even');
getElementsByClassName
var els = document.getElementsByClassName('even');
jQuery: mixed selector
var els = $('li.even');
querySelectorAll: mixed selector
var els = document.querySelectorAll('li.even');

Run results for: Get elements by class: jQuery vs querySelectorAll vs getElementsByClassName (Jquery 3.3.1)

Compare various methods of obtaining a group of elements identified by class name

jQuery

querySelectorAll

getElementsByClassName

jQuery: mixed selector

querySelectorAll: mixed selector