Run results for: classList.contains vs. loop vs regex

Run details:

User agent: Mozilla/5.0 (Linux; Android 11; RMX2083 Build/RKQ1.200928.002; wv) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 Chrome/93.0.4577.62 Mobile Safari/537.36 Line/11.16.2/IAB

Browser: Chrome Mobile 93

Operating system: Android

Device Platform: Mobile

Date tested: 3 years ago

Test name	Executions per second
Use hasClass shorthand	939984.9 Ops/sec
Use classList	1029821.9 Ops/sec
Use classname match	452698.3 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");
Use classname match
test_element.className.match('bar'); test_element.className.match('baz');

Run results for: classList.contains vs. loop vs regex

Use hasClass shorthand

Use classList

Use classname match