Run results for: className vs setAttribute vs classList

Run details:

User agent: Mozilla/5.0 (iPhone; CPU iPhone OS 14_7_1 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/14.1.2 Mobile/15E148 Safari/604.1

Browser: Mobile Safari 14

Operating system: iOS 14.7.1

Device Platform: Mobile

Date tested: 2 years ago

Test name	Executions per second
className	7806.6 Ops/sec
setAttribute	6543.2 Ops/sec
classList	5667.4 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"); }