Size: 21 Insole length: 13cm/5.12 Recommended age: 6-12 Months US : 7 UK: 6.5 EU: 21 Suitable for: Toddler Size: 22 Insole length: 13.5cm/5.31 Recommended age: 12-18 Months US : 7.5 UK: 7 EU: 22 Suitable for: Toddler Size: 23 Insole length: 14cm/5.51 Recommended age: 18-24 Months US : 8 UK: 7.5 EU: 23 Suitable for: Toddler Size: 24 Insole length: 14.5cm/5.71 Recommended age: 2-2.5 Years US : 8.5 UK: 8 EU: 24 Suitable for: Toddler Size: 25 Insole length: 15cm/5.91 Recommended age: 2.5-3 Years US : 9 UK: 8.5 EU: 25 Suitable for: Toddler Size: 26 Insole length: 15.5cm/6.10 Recommended age: 3-3.5 Years US : 9.5 UK: 9 EU: 26 Suitable for: Toddler Size: 27 Insole length: 16cm/6.30 Recommended age: 3.5-4 Years US : 10 UK: 9.5 EU: 27 Suitable for: Toddler Size: 28 Insole length: 16.5cm/6.50 Recommended age: 4-4.5 Years US : 10.5 UK: 10 EU: 27.5 Suitable for: Little Child Size: 29 Insole length: 17.5cm/6.89 Recommended age: 5-5.5 Years US : 11.5 UK: 11 EU: 28.5 Suitable for: Little Child Size: 30 Insole length: 18cm/7.09 Recommended age: 5.5-6 Years US : 12 UK: 11.5 EU: 29.5 Suitable for: Little Child