Run results for: className vs. setAttribute vs. classList

Run details:

User agent: Mozilla/5.0 (Linux; Android 6.0.1; SM-G550 Build/MMB29K; wv) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/49.0.2623.105 Mobile Safari/537.36

Browser: Chrome Mobile 49

Operating system: Android 6.0.1

Device Platform: Mobile

Date tested: 5 years ago

Test name	Executions per second
className	453.8 Ops/sec
setAttribute	301.7 Ops/sec
classList	440.5 Ops/sec

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"); }