How should swim fins fit?
More important than a number size is how your swim fins should fit and feel.
When you put the fins on they need to be snug. Your toes should be at the end of the foot pocket comfortably but not smashed.
Getting the fin on and off should be easy. Slipping them on like slippers means they are way too loose and cramming your foot in to make it fit is also bad.
If the fin is too tight or loose you will run into a lot of problems; muscle cramps, loosing your fins out in the water, cuts, ulcers and general discomfort. Not fun. So lets make sure they fit you right. They need to be comfortably snug.
An indication that the fins are too small is if your foot is bulging on the top of the foot pocket, your toes are crunched and they are difficult to take off your feet.
Indications that they are too loose would be if there is a gap between your ankle and the heel strap and when you move the fin around you can feel a gap from your foot and the fin pocket. In both cases your feet should fill these gaps so a smaller fin will be needed.
Ok now that we have that out of the way lets get to the fun stuff by going to the Fin Comparison Chart to get your fins.