I bought 2 pairs of these, one brown and one black. The sizing seems off, they are huge. They slide and rub my heel to the point that it is painful. I've played around with adding an insole from another pair of shoes and this seems to help, but I am a little resentful of having to do this to $40 plastic shoes. They are very cute and so versatile. Just be sure to order a size smaller than you would normally wear.

Note: I have an older pair of crocs that are a size 5 and fit perfectly (made in mexico) and these were also a 5 and are huge (made in china). Not sure if something changed in sizing when they changed the location for manufacturing.

Update: I found a solution to the weird fit of these shoes: throw them in the dryer on high with a beach towel for about 20 minutes and they shrink. Put them on your feet when you take them out and they will mold to your feet. I read online to try this and did not believe it would work but it really did! SO happy, now they are perfect.