Size 6-8 fits my 90th percentile three-year-old perfectly. He wears a size 10.5 shoe. Thankfully, they have some stretch to them so they should fit him for the rest of the summer. I was hoping there would be enough color options to match everything in his summer wardrobe but they're more limited than I had thought. I would prefer the shade of lighter blue to be more of a blue-green and Id add at least one black color option.