getElementsByClassName VS querySelectorAll

JavaScript performance comparison

Revision 54 of this test case created

Info

I wanted to see how well does jQuery performs on class selectors…

Preparation code

<script src="//ajax.googleapis.com/ajax/libs/jquery/1.10.2/jquery.min.js"></script>
<script>
var $$ = function(theClass) {
  return $(document.getElementsByClassName(theClass));
}
var nodes;
</script>
<div id="wrap">
  <ul>
    <li>
      <a href="#" name="name" class="classname">item 1</a>
    </li>
    <li>
      <a href="#" name="name" class="classname">item 2</a>
    </li>
    <li>
      <a href="#" name="name" class="classname">item 3</a>
    </li>
    <li>
      <a href="#" name="name" class="classname">item 4</a>
    </li>
    <li>
      <a href="#" name="name" class="classname">item 5</a>
    </li>
    <li>
      <a href="#" name="name" class="classname">item 6</a>
    </li>
    <li>
      <a href="#" name="name" class="classname">item 7</a>
    </li>
    <li>
      <a href="#" name="name" class="classname">item 8</a>
    </li>
    <li>
      <a href="#" name="name" class="classname">item 9</a>
    </li>
    <li>
      <a href="#" name="name" class="classname">item 10</a>
    </li>
  </ul>
</div>

Preparation code output

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Testing in unknown unknown
Test Ops/sec
getElementsByClassName
nodes = document.getElementsByClassName('classname');
pending…
jQuery $(.class)
nodes = $(".classname");
pending…
jquery('tag.class')
nodes = $("a.classname");
pending…
jQuery hybrid selector fn
nodes = $$('classname');
pending…
jQuery id > class
nodes = $('#wrap').find('.classname');
pending…

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