Run results for: GetElementById vs GetElementByTag v2

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/117.0.0.0 Safari/537.36

Browser: Chrome 117

Operating system: Mac OS X 10.15.7

Device Platform: Desktop

Date tested: one year ago

Test name	Executions per second
GetElementById	10030170.0 Ops/sec
GetElementByTag	7159898.5 Ops/sec
GetElementByClassname	7931047.5 Ops/sec

HTML Preparation code:

<div id="unique" class="unique" name="unique" data-unique="1">test</div>
<unique-custom id="unique-custom" class="unique-custm" name="unique-custom" data-unique-custom="1">unique custom</unique-custom>

Script Preparation code:

var i, imax;
var doc = document;
var customElementRegistry = window.customElements;
customElementRegistry.define("unique-custom", class MyCustomElement extends HTMLElement {
  constructor() {
    // Always call super first in constructor
    super();
  }});

Tests:

GetElementById
var test = doc.getElementById('unique').innerHTML;
GetElementByTag
var formelem = doc.getElementsByTagName('unique-custom')[0].innerHTML;
GetElementByClassname
var test = doc.getElementsByClassName('unique')[0].innerHTML;

Run results for: GetElementById vs GetElementByTag v2

GetElementById

GetElementByTag

GetElementByClassname