These are just a little too big for my 4.5-yo twins, but most crocs don't seem to fit perfectly.  My girls love them though so I didn't return them.  The biggest problem is that they rub on the inside of their ankles and back of the heels, causing a bit of blistering.  I had to make my girls wear these with socks.  The blisters healed after a few weeks of wearing them with socks, but started to come back again when worn without socks for a few days so we're stuck wearing them with socks all the time.  It's a shame.