Run results for: classList.contains vs.

Run details:

User agent: Mozilla/5.0 (iPhone; CPU iPhone OS 14_3 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) CriOS/85.0.4183.109 Mobile/15E148 Safari/604.1

Browser: Chrome Mobile iOS 85

Operating system: iOS 14.3

Device Platform: Mobile

Date tested: 3 years ago

Test name	Executions per second
Use hasClass shorthand	2589481.0 Ops/sec
Use classList	4024731.0 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");

Run results for: classList.contains vs.

Use hasClass shorthand

Use classList