I usually wear an 8 1/2 so I went up to a 9 and they fit great.  You need to toughen up the skin on the back of your heels because they do rub like a new pair of shoes, but once "broken in" they have been fine.  I wear them at a lake with a sandy bottom, stony bottom, and mucky bottom and they protect my feet just fine!  They don't let in the sand and small gravel so I don't have to keep taking them off and rinsing them out.  Well worth the price.  I'll never buy another water shoe!

good protection in the water, heavy duty, comfortable

The shoes are too tight at the very top. I wore them today to swim and when I took them off, I had marks on top of both feet where they cut into my skin. The rest of the shoe is perfect for swimming. I'm hoping they will loosen some with wear. I hope I can wash them in the washing machine, but they came with no instructions of any kind.

I teach water aerobics in addition to spending lots of time at the beach.  This is the first shoe I've found that forms to the foot.  You can swim in this shoe because it doesn't trap lots of water.  It also has great traction on slippery rocks or glossy pool tiles.  I wish it came in 1/2 sizes.  I ordered up.  I probably should have ordered down.  Fits my wide foot.