Gender: unisex season: summer If you have any questions please feel to contact us. Size chart: Size:15 US:5 UK:4.5 EU:21 Recommended age:6-9 Months Insole Length:12.5cm/4.92 Suitable For: Size:16 US:5.5 UK:5 EU:22 Recommended age:9-12 Months Insole Length:13cm/5.12 Suitable For: Size:17 US:6 UK:5.5 EU:23 Recommended age:12-18 Months Insole Length:13.5cm/5.31 Suitable For: Size:18 US:6.5 UK:6 EU:23.5 Recommended age:18-24 Months Insole Length:14cm/5.51 Suitable For: Size:19 US:7 UK:6.5 EU:24 Recommended age:2-2.5 Years Insole Length:14.5cm/5.71 Suitable For:Toddler Size:22 US:7.5 UK:7 EU:25 Recommended age:2.5-3 Years Insole Length:14.7cm/5.79 Suitable For:Toddler Size:23 US:8 UK:7.5 EU:25.5 Recommended age:3-3.5 Years Insole Length:15cm/5.91 Suitable For:Toddler Size:24 US:9 UK:8.5 EU:26 Recommended age:3.5-4 Years Insole Length:15.5cm/6.10 Suitable For:Toddler Size:25 US:9.5 UK:9 EU:27 Recommended age:4-4.5 Years Insole Length:16cm/6.30 Suitable For:Little Child