DESCRIPTION How to Choose the Size? The Size isn`t Standard US Size or Euro Size, please choose the size according to Foot Length. Insole Length= Foot Length + 0.5 cm~1cm CN 26insole 16.5cm CN 27insole 17.0cm CN 28insole 17.5cm CN 29insole 18.0cm CN 30insole 18.5cm CN 31insole 19.0cm CN 32insole 19.5cm CN 33insole 20.0cm CN 34insole 20.5cm CN 35insole 21cm Note: This shoe size is EUR size, the other will be different! Of course, you can also purchase according to the length of the insole! Children shoe size chart: EUR size 21-30 Suitable for 0-6 years old EUR size 31-35 Suitable for 6-10 years old All measurement in cm,please note 1 cm=0.39 inch,1 inch=2.54 cm