Size Chart:Size:21 Insole Length:13.5CM/5.3" Recommended Age:15-18Months EU:22.5 UK:5.5 US:6.5 Suitable For:ToddlerSize:22 Insole Length:14CM/5.5" Recommended Age:18-24Months EU:23 UK:6 US:7 Suitable For:ToddlerSize:23 Insole Length:14.5CM/5.7" Recommended Age:2-2.5Years EU:23.5 UK:7 US:8 Suitable For:ToddlerSize:24 Insole Length:15CM/5.9" Recommended Age:2.5-3Years EU:24 UK:7.5 US:8.5 Suitable For:ToddlerSize:25 Insole Length:15.5CM/6.1" Recommended Age:3-3.5Years EU:25 UK:8 US:9 Suitable For:ToddlerSize:26 Insole Length:16CM/6.3" Recommended Age:3.5-4Years EU:26 UK:8.5 US:9.5 Suitable For:Little KidSize:27 Insole Length:16.5CM/6.5" Recommended Age:4-4.5Years EU:27 UK:9 US:10 Suitable For:Little KidSize:28 Insole Length:17CM/6.7" Recommended Age:4.5-5Years EU:28 UK:10 US:11 Suitable For:Little KidSize:29 Insole Length:18CM/7.1" Recommended Age:5-5.5Years EU:29 UK:11 US:12 Suitable For:Little KidSize:30 Insole Length:18.5CM/7.3" Recommended Age:6.5-7Years EU:30 UK:11.5 US:12.5 Suitable For:Little KidSize:31 Insole Length:19CM/7.5" Recommended Age:7.5-8Years EU:31 UK:12 US:13 Suitable For:Little KidSize:32 Insole Length:19.5CM/7.7" Recommended Age:8.5-9Years EU:31.5 UK:12.5 US:13.5 Suitable For:Little KidSize:33 Insole Length:20CM/7.9" Recommended Age:9-9.5Years EU:32 UK:13 US:1 Suitable For:Big KidSize:34 Insole Length:20.5CM/8.1” Recommended Age:9.5-10Years EU:32.5 UK:13.5 US:1.5 Suitable For:Big KidSize:35 Insole Length:21.5CM/8.5" Recommended Age:10.5-11Years EU:33.5 UK:1.5 US:2.5 Suitable For:Big KidSize:36 Insole Length:22CM/8.7" Recommended Age:11-11.5Years EU:34 UK:2 US:3 Suitable For:Big Kid