This was true a few years ago. Haven't all major browsers made it so that when you zoom in, it does actually zoom px (as well as images, etc)? (example: http://

This was true a few years ago. Haven't all major browsers made it so that when you zoom in, it does actually zoom px (as well as images, etc)? (example: http://cl.ly/1O2d3s1Y3R213O1B0U1x http://cl.ly/1O2d3s1Y3R213O1B0U1x) Meaning that, basically, you use the following rules: px = you want it to be x pixels when not zoomed at all em = you want it to be relative to the parent div (ex: parent is 10px + child is 1.1em = child is 11px) Personally, I find em to be a bit too susceptible to breakage since they're relative to the size of the parent (which is relative to the size of their parent, etc). Using rem is interesting, however I disagree with most of what was said in this post.