getElementById vs. getElementsByClassName vs. querySelector

JavaScript performance comparison

Revision 16 of this test case created

Info

Compare the speed of getElementById to getElementsByClassName to querySelector

Preparation code

<p id="foo" class="my-foo">Foo</p>
<p id="bar" class="my-bar">Bar</p>
<p id="baz" class="my-baz">Baz</p>

Preparation code output

Foo

Bar

Baz

Test runner

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Testing in unknown unknown
Test Ops/sec
getElementById
var bar = document.getElementById("bar");
pending…
querySelector
var bar = document.querySelector("#bar");
pending…
getElementsByClassName
var bar = document.getElementsByClassName("my-bar");
pending…

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Revisions

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