Run results for: className vs setAttribute vs classList

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/90.0.4430.41 YaBrowser/21.5.0.579 Yowser/2.5 Safari/537.36

Browser: Yandex Browser 21

Operating system: Windows

Device Platform: Desktop

Date tested: 2 years ago

Test name	Executions per second
className	3157.9 Ops/sec
setAttribute	2080.7 Ops/sec
classList	2154.4 Ops/sec

HTML Preparation code:

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

Script Preparation code:

var element = document.getElementById('foo');

Tests:

className
var i = 1000; while (i--) { element.className = "bar"; }
setAttribute
var i = 1000; while (i--) { element.setAttribute("class", "bar"); }
classList
var i = 1000; while (i--) { element.classList.add("bar"); }