My dh decided to wash ours right before our trip in February. Of course, it was winter so we didn't wear them before the trip. When we arrived - they were too small! Yup, he put them in the dishwasher! Mine shrank at least a full size, the kids could get their feet in but they were tight. We ended up buying new pairs for the kids at World of Disney just so they would be comfortable around the parks - they live in their crocs while we're there. I didn't bother replacing mine as I only wear them occasionally anyways. My advice: wash by hand!