Run results for: className vs classList add and remove

Run details:

User agent: Mozilla/5.0 (Windows NT 6.3; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/107.0.0.0 Safari/537.36

Browser: Chrome 107

Operating system: Windows 8.1

Device Platform: Desktop

Date tested: 2 years ago

Test name	Executions per second
className	1035.4 Ops/sec
classList	839.4 Ops/sec

HTML Preparation code:

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

Tests:

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