I wear a men's 11 or 11.5 in running shoes. I ordered a Large, nope too small. Returned for an XL, nope too small. Returned for an XXL and they sent me two left shoes. Still a little snug. A men's 11 is a XXXL? Wow. I have a normal width food, nothing special. Go to the shoe store and ask for an 11 and it fits every time.