Hi Uriah. If you are a men's 10.5 US with normal width add a half size to make it a men's 11 US. (You'll appreciate the extra half size due to the high heel) Then order the US size 13. The size chart works well for ladies sizing so you have to go two sizes higher - a ladies 13 US should work well for a men's 11 US. I am a men's 9 US and I ordered the size 11 US in the sneaker boot and it fit well. If it is a little snug when you get it you can always scratch out the spongy insole insert in the toe area which will give you a little extra wiggle room. If you are a wide width you'll probably want to go up to a size 14 US.