Run results for: Set className vs. setAttribute vs classList

Run details:

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:147.0) Gecko/20100101 Firefox/147.0

Browser: Firefox 147

Operating system: Mac OS X 10.15

Device Platform: Desktop

Date tested: 7 months ago

Benchmark engine: Benchmark.js

setAttribute

130/s

className

128/s

classList

22/s

View exact numbers

HTML Preparation code:

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

Tests:

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