I'm 10.5 in normal shoes normally. I've been wearing 44 in most cycling shoes so that being said the shimano sizing indicates I should be in 45 shimano but ended up in 44 wide. I could have gotton away with standard 44 or 44.5 but the slightly wider toe box in 44 felt great. If I hadn't tried them on first I probably would have purchased the wrong size initially. I did a full review on these shoes at 1010 Human Performance