Benchmark: classList.contains vs.

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");

Rendered benchmark preparation results:

Previous results

Test case name	Result
Use hasClass shorthand
Use classList

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Latest run results:

Run details: (Test run date: 3 months ago)

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

Browser/OS: Firefox 115 on Windows

Test name	Executions per second
Use hasClass shorthand	3814674.0 Ops/sec
Use classList	653460000.0 Ops/sec

classList.contains vs. (version: 0)