Run results for: classList.contains vs.

Run details:

User agent: Mozilla/5.0 (Windows NT 6.3; Win64; x64; rv:70.0) Gecko/20100101 Firefox/70.0

Browser: Firefox 70

Operating system: Windows 8.1

Device Platform: Desktop

Date tested: 4 years ago

Test name	Executions per second
Use hasClass shorthand	2536281.0 Ops/sec
Use classList	6445918.0 Ops/sec

HTML Preparation code:

<div id="foo" class="bar baz"></div>

Script Preparation code:

var test_element = document.getElementById("foo");

Tests:

Use hasClass shorthand
function hasClass(element, classes) { classes = classes.split(' '); for (var i = 0; i < classes.length; i++) { if (!element.classList.contains(classes[i])) { return false; } } return true; }; hasClass(test_element, "bar baz");
Use classList
test_element.classList.contains("bar"); test_element.classList.contains("baz");