Run results for: className.indexOf vs. classList.contains

Run details:

User agent: Mozilla/5.0 (Linux; Android 9; LG-H870) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/80.0.3987.149 Mobile Safari/537.36

Browser: Chrome Mobile 80

Operating system: Android

Device Platform: Mobile

Date tested: 4 years ago

Test name	Executions per second
className	18366.2 Ops/sec
classList	9175.1 Ops/sec

HTML Preparation code:

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

Tests:

className
var element = document.getElementById("foo"); var i = 1000; while (i--) { if (element.className.indexOf("test") !== -1) {} }
classList
var element = document.getElementById("foo"); var i = 1000; while (i--) { element.classList.contains("test"); }