Size number often different in different country, but your bare foot length would never change , so you must measure your bare foot with a ruler , then choose size with chart below . Bare Foot Length 24.5cm, EUR size 39, Choose shoes size 7.5; Bare Foot Length 25cm, EUR size 40, Choose shoes size 8; Bare Foot Length 25.5cm, EUR size 41, Choose shoes size 8.5 ; Bare Foot Length 26cm, EUR size 42, Choose shoes size 9; Bare Foot Length 26.5cm, EUR size 43, Choose shoes size 9.5; Bare Foot Length 27cm, EUR size 44, Choose shoes size 10; fit small than usual,please choose one size bigger than the shoes size chart