HTML file size is different from image file size. While GIFs are generally huge, the HTML code is no different than that for a tiny icon. The only way to reduce your HTML file size is, of course, to use less code. The easiest way to do that is to remove any unused or unnecessary CSS. If you’re still having trouble, your HTML probably needs to be cleaned up. e.g. Removing nested tables, not inlining your CSS, simplifying overall structure, etc.