Shoe Size - 10 / 44 - Sock Size - Large
Shoe Size - Women's 40 - Sock Size - Small (or Medium)
Here is a handy little guide to keep in mind when you're choosing your socks. Just remember that part of this comes down to personal preference. If you're like me (size 10 - 10.5 shoe) I can fit into a medium if I have to, but they're tight, what I prefer is to go with a large. It's up to you to figure out what you like. I mean, that is pretty much the reasoning behind most of this stuff anyway, isn't it?
The Athletic Socks
Small » Women - 8 & under — Men - 7 & under — EU - 36 - 39.5
Medium » Women - 8.5 - 10.5 — Men - 7.5 - 9 — EU - 40 - 42.5
Large » Women - 11 - 13 — Men 9.5 - 11.5 — EU - 43 - 45.5
XL » Women - 13+ — Men - 12+ — EU - 46+