Run results for: Has class className vs. classList

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/71.0.3578.98 Safari/537.36

Browser: Chrome 71

Operating system: Windows

Device Platform: Desktop

Date tested: 5 years ago

Test name	Executions per second
className	1818.7 Ops/sec
setAttribute	19736.5 Ops/sec

HTML Preparation code:

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

Tests:

className
var element = document.getElementById("foo"); var i = 1000; while (i--) { new RegExp('(^| )(one)( |$)', 'gi').test(element.className); }
setAttribute
var element = document.getElementById("foo"); var i = 1000; while (i--) { element.classList.contains('one'); }