getElementById vs. getElementsByClassName vs. querySelector vs. jQuery

JavaScript performance comparison

Revision 57 of this test case created

Info

Compare the speed of getElementById to getElementsByClassName to querySelector to jQuery returns of each of those selectors.

Preparation code

<script src="//ajax.googleapis.com/ajax/libs/jquery/1/jquery.min.js">
</script>
<p id="foo" class="my-foo">
  Foo
</p>
<p id="bar" class="my-bar">
  Bar
</p>
<div id="poo" class="my-poo">
  <div id="par" class="my-bar">
    <div id="paz" class="my-bar">
      <span id="baz" class="my-baz">
        Baz
      </span>
    </div>
  </div>
</div>

Preparation code output

Foo

Bar

Baz

Test runner

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Testing in unknown unknown
Test Ops/sec
getElementById
var baz = document.getElementById("baz");
pending…
querySelector (ID)
var baz = document.querySelector("#baz");
pending…
jQuery ID Selector
var baz = $("#baz");
pending…
getElementsByClassName
var baz = document.getElementsByClassName("my-baz");
pending…
querySelector (Class)
var poo = document.querySelector(".my-baz");
pending…
getElementsByTagName
var span = document.getElementsByTagName("span")
pending…

Compare results of other browsers

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