Recommended to buy half size smaller than your normal size.
I highly recommend getting a half size smaller than whatever size you usually wear. The shoes stretch enough to fit your feet, but considering their purpose (use in water) its better to be tighter than a little loose.I used these for walking through a shallow river on slippery rocks. I had to tighten the straps all the way so they would stay snug on my feet. Im a size 26 (Japan) and bought a size 26. There is a tiny bit of space at the front of my toes. Sand/gravel slips in around the ankles despite fully pulling the strings tight. Bottom is kind of thin so I felt every rock under my feet. Bottom also doesnt have great grip. The insole slips out easily on one of the shoes when taking them off and sometimes moves around when walking.If you are planning to do a lot with your shoes, I would recommend buying something higher quality. If not, then these should be good enough for some light water play.