Run results for: className vs. setAttribute vs. classList

Run details:

User agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:135.0) Gecko/20100101 Firefox/135.0

Browser: Firefox 135

Operating system: Ubuntu

Device Platform: Desktop

Date tested: one year ago

className

11K/s

setAttribute

7K/s

classList

4K/s

View exact numbers

HTML Preparation code:

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

Tests:

className
var element = document.getElementById("foo"); var i = 1000; while (i--) { element.className = "bar"; }
setAttribute
var element = document.getElementById("foo"); var i = 1000; while (i--) { element.setAttribute("class", "bar"); }
classList
var element = document.getElementById("foo"); var i = 1000; while (i--) { element.classList.add("bar"); }