Run results for: getElementById vs querySelector vs getElementsByClassName vs getElementsByName 2

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:86.0) Gecko/20100101 Firefox/86.0

Browser: Firefox 86

Operating system: Windows

Device Platform: Desktop

Date tested: 3 years ago

Test name	Executions per second
getElementById	965400320.0 Ops/sec
getElementsByClassName	6526180.0 Ops/sec
getElementsByName	6459203.5 Ops/sec
querySelectorAll	1031766.4 Ops/sec

HTML Preparation code:

<div id="testdiv1">
  <div id="testdiv2" class="unique2" name="unique2" data-unique="2">test</div>
  <div id="testdiv3" class="unique3" name="unique3" data-unique="3">test</div>
</div>

Script Preparation code:

var i, imax;
var doc = document;

Tests:

getElementById
var test = doc.getElementById('testdiv2').innerHTML;
getElementsByClassName
var test = doc.getElementsByClassName('unique2')[0].innerHTML;
getElementsByName
var test = doc.getElementsByName('unique2')[0].innerHTML;
querySelectorAll
var test = doc.querySelectorAll("[data-unique='2']")

Run results for: getElementById vs querySelector vs getElementsByClassName vs getElementsByName 2

Test performance of different ways of get just one particular DOM element

getElementById

getElementsByClassName

getElementsByName

querySelectorAll