Size guide:5 US Infants = 21 EUR = 11 cm6 US Infants = 22 EUR = 12 cm7 US Infants = 23 EUR = 13 cm8 US Infants = 24 EUR = 14 cm9 US Infants = 25 EUR = 15 cm10 US Infants = 26 EUR = 16 cm