First of all, I am a 6.5M in women's shoes regularly and in athletic shoes except for Converse, and in Crocs I am almost always men's 4/women 6 or kids j4. These are roomy and it's entirely possible I would fit into a five but I might not be able to slip them on without touching them, and they might rip my ankles just so you know. Also if you're wondering about what size you wear in children's as opposed to women's or men's, if you have a smaller foot -- I have discovered that at youth sizes are just small men sizes or unisex I guess. Men's size 4 is the same size as kids 4, big kids 4, or J or youth or whatever they call it.I find these to be non-slip, I can step out onto a wet or cold patio or porch, without stopping to lean down and pull on shoes or wellies. These are supposed to fit in a roomy way, because you're supposed to stick your foot down in them and wiggle it around and they just pop on!I have the crush boot which is without the fur and then this one for colder weather. I wish people in reviews with stop commenting that these are too big, they are supposed to be bigger and roomier so they will easily wiggle on to your foot with little effort. I like the roominess because my pant legs will slide into them and keep dry and clean.Everyone should have a plain pair and a furry pair. They're fantastic. The only issue I have found is that special colors such as glitter silver whatever tend to be on the stiffer side and might rub your ankles. I know that the non-fur kind does this in those special colors. These are perfect though. The fur is brilliant and warm and pretty. I wish they had them in every color. I'm trying to figure out do I really need more than one pair of these. They're a little pricey but there are discounts all the time here. They're cute as they can be, and don't look like your typical Crocs in case you're hesitating.