I am a U.S. size 12 and normally I would order just that, but I had a feeling that I should size up and I probably should’ve sized up twice. I still love how size 13 fits, but I like for there to be a little bit of extra sandal to walk in. Nonetheless I’m happy with them, only “negative” thing I have to say is the foot straps are a little loose for my liking. If they were 1cm or two shorter they’d fit a little more snug.