getElementById vs. getElementsByClassName vs. querySelector vs. jQuery

JavaScript performance comparison

Revision 24 of this test case created by

Preparation code 

<script src="https://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

<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>

Test runner

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Testing in CCBot 2.0.0 / Other 0.0.0
Test Ops/sec
getElementById 
var bar = document.getElementById("bar");
var poo = document.getElementById("poo");
 pending…
querySelector (ID) 
var bar = document.querySelector("#bar");
var poo = document.querySelector("#poo");
 pending…
jQuery ID Selector 
var bar = $("#bar");
var poo = $("#poo");
 pending…
getElementsByClassName 
var bar = document.getElementsByClassName("my-bar");
 pending…
querySelector (Class) 
var poo = document.getElementById("poo").querySelector(".my-baz");
 pending…
jQuery Class Selector 
var bar = $(document.getElementById("poo").querySelector(".my-baz"));
 pending…

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Revisions

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