Run results for: classList.contains vs.

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:109.0) Gecko/20100101 Firefox/115.0

Browser: Firefox 115

Operating system: Windows

Device Platform: Desktop

Date tested: 2 years ago

Use classList

653.5M/s

Use hasClass shorthand

3.8M/s

View exact numbers

Test name	Executions per second
✓ Use classList	653,459,968 Ops/sec
Use hasClass shorthand	3,814,674 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");