Run results for: className vs classList

Run details:

User agent: Mozilla/5.0 (X11; Linux x86_64; rv:109.0) Gecko/20100101 Firefox/115.0

Browser: Firefox 115

Operating system: Linux

Device Platform: Desktop

Date tested: 3 months ago

Test name	Executions per second
className	2.1 Ops/sec
classList	1550.0 Ops/sec

HTML Preparation code:

<div id="foo"></div>

Tests:

className
var element = document.getElementById("foo"); var i = 1000; while (i--) { element.className += "bar "; }
classList
var element = document.getElementById("foo"); var i = 1000; var cl = element.classList; while (i--) { cl.add("bar"); }