Crocs don't fit like other shoes. They should fit you very loosely with the sides of your foot not touching the sides or the front of the shoe. Your toes should not touch any part of the shoe. There should be 1/4" to 1/2" of space in front of your toes and behind your heel when your foot is centered on the footbed of the shoe. The shoes should be loose when purchased. There should be no pressure points, ever!
The strap should be loose enough not to pull your foot toward the front of the shoe. If the strap is too tight, you can loosened it by gently working your fingers around the strap to stretch it. The strap can also be worn toward the front of the shoe instead of behind the ankle.
It is recommended that Crocs footwear be purchased in a size 1/2 to 1 full size larger than a normal shoe size.
Crocs is made from a resin material that has a memory and will mould to the shape of your foot when worn. They will stay at the proper fit after one or two wearings.