Shoes are super cute and comfy but definitely order a size up. My son measures a 3.5 (have a sizer at home) so we purchased 3 different shoes in a size 4 for school. Both of the other brands were perfect and had room these shoes, his toes were right at the end. Had to try both a 4.5 and 5 to settle on the 5. So after 3 pairs of these I've found every single pair fit a size smaller than marked.