I normally wear an 8, and the 8 was far too big for me in these.  I had two choices, tighten the heel strap down to the point where it had a crease, like wearing pants that are too big with a belt does (this was extremely uncomfortable), or having them way loose, which causes the heel to rub up and down and form blisters.

I returned the 8's for 7.5's, and the right foot was fine, but the left was still too big. (everyone's feet are slightly different sized like that).

With a shoe like this, meant to be worn sockless, it really needs to fit like a glove, so even a half size off is no good.

Ended up liking the shoe enough to keep the 7.5's, and ordered a second pair in size 7.

7 on left foot, 7.5 on right foot, works like a charm.  Silly perhaps to spend so much to get one working pair, but I really liked them, so it was worth it for me.  I of course have a mismatched pair sitting in my closet now as well, which I don't know what I'll do with, lol.

Great shoe for the park if you are planning on getting wet fishing, river walking, scrambling, trail running, hiking, etc.  Good traction on mossy rocks, creekbeds, etc.  Would recommend, but beware of sizing issues as I said.