Run results for: className vs. setAttribute vs. classList v4

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/121.0.0.0 Safari/537.36

Browser: Chrome 121

Operating system: Mac OS X 10.15.7

Device Platform: Desktop

Date tested: 2 years ago

classList

2K/s

className

2/s

View exact numbers

Test name	Executions per second
✓ classList	1,783 Ops/sec
className	2 Ops/sec

HTML Preparation code:

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

Tests:

className
var element = document.getElementById("foo"); var i = 1000; while (i--) { element.className += " bar bar2 bar3"; }
classList
var element = document.getElementById("foo"); var i = 1000; while (i--) { element.classList.add("bar"); element.classList.add("bar2"); element.classList.add("bar3"); }