$(document).ready() fires too early

Question

So, I need to know the width of an element with javascript, the problem I have is that the function fires too early and the width changes when the css is tottally applied. A

Answer 1

If you rely on external content to be already loaded (e.g. images, fonts), you need to use the window.load event

$(window).on("load", function() {
    // code here
});

The behaviour of these events is described in this article:

There is [a] ready-state however known as DOM-ready. This is when the browser has actually constructed the page but still may need to grab a few images or flash files.

Edit: changed syntax to also work with jQuery 3.0, as noted by Alex H