One of the most performant ways to toggle an element with JavaScript is to apply and remove a class. Paul Irish pointed out last year that using jQuery’s .hide(), .show(), and .toggle() methods are very costly. I’ve used/am currently using each of these, as they are really easy to understand and implement. However, you’ll see that a plain JavaScript approach isn’t too difficult.

For my site, I needed a toggle for the menu on small screens. I used the following to add and remove a class named ‘open’, which has the proper styles to show the menu. In this case, it is performed when an element with the class of ‘toggle’ is clicked.

var menu = document.querySelector('.toggle');
menu.onclick = function() {