Run results for: classList.contains VS dataset

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/133.0.0.0 Safari/537.36 Edg/133.0.0.0

Browser: Chrome 133

Operating system: Windows

Device Platform: Desktop

Date tested: one year ago

classList

14K/s

className

7K/s

View exact numbers

Test name	Executions per second
✓ classList	13,710 Ops/sec
className	6,970 Ops/sec

HTML Preparation code:

<div id="foo" class="test" data-class-test="1" ></div>

Tests:

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