Benchmark Run Result for: classList.contains vs.

Test name	Executions per second
Use hasClass shorthand	4702778.0 Ops/sec
Use classList	18736452.0 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");