Run results for: setAttribute("class", "foo") vs classList.add("foo")

Run details:

User agent: Mozilla/5.0 (Windows NT 6.3; rv:75.0) Gecko/20100101 Firefox/75.0

Browser: Firefox 75

Operating system: Windows 8.1

Device Platform: Desktop

Date tested: 4 years ago

Test name	Executions per second
setAttribute	441.5 Ops/sec
classList	200.4 Ops/sec

HTML Preparation code:

<div id="container"></div>

Script Preparation code:

var container = document.getElementById("container");

Tests:

setAttribute
for (let i = 0; i < 100; ++i) { var div = document.createElement("div"); div.setAttribute("class", "foo"); container.appendChild(div); }
classList
for (let i = 0; i < 100; ++i) { var div = document.createElement("div"); div.classList.add("foo"); container.appendChild(div); }