These are my favorite vibras. I wear size 41, women or men, when I buy these shoes, they are based on EU sizes, which refer to your foot length. My size is 8.5-9 women or 6.5-7 men US, but these shoes are always 41. However, I have found that some of them pinch their little toes or feel uncomfortable between their toes, they also have different ones styles so always check their actual website to find the right conversation for a specific shoe as this sometimes changes. For example, water shoes might work, but they might suggest a size for insulated walking shoes.