In order to avoid the unnecessary trouble caused by the shoe size problem, we have prepared the size of the shoes for you, please refer to the following sizes to purchase 5.5 US Toddler = foot length 5.12 inches = 13 cm = label 21 6 US Toddler = foot length 5.32 inches = 13.5 cm = label 22 6.5 US Toddler = foot length 5.52 inches = 14 cm = label 23 7 US Toddler = foot length 5.71 inches = 14.5 cm = label 24 7.5 US Toddler = foot length 5.91 inches = 15 cm = label 25 8 US Toddler = foot length 6.10 inches = 15.5 cm = label 26 9 US Toddler = foot length 6.38 inches = 16.2 cm = label 27 10 US Toddler = foot length 6.61 inches = 16.8 cm = label 28 10.5 US Little Kid= foot length 6.85 inches = 17.4 cm = label 29 11 US Little Kid = foot length 7.09 inches = 18 cm = label 30 12 US Little Kid = foot length 7.32 inches = 18.6 cm = label 31 12.5 US Little Kid = foot length 7.56 inches = 19.2 cm = label 32 13 Little Kid = foot length 7.81 inches = 19.8 cm = label 33 1 Little Kid = foot length 8.03 inches = 20.4 cm = label 34 1.5 Little Kid = foot length 8.27 inches = 21 cm = label 35 2.5 Little Kid = foot length 8.51 inches = 21.6 cm = label 36 3 Little Kid = foot length 8.74 inches = 22.2 cm = label 37 Notes: If you have tapered big toe, it is recommended to order one size up. If you have wide feet, it is recommended to order one size up.