The size chart shows the inner length and width of each shoe model (EU shoe size). BeLenka recommend adding a leeway (the leeway measures the space between a customer's longest toe and the shoe itself) of 0.5 - 1.2cm to get the ideal shoe size for the customer. Should customers have any questions, contact BeLenka at BeLenka’s e-mail info@belenka.com, BeLenka will be happy to help.