12-18 Months (21#: Foot Length/insole Length: 13.0 cm/13.5 cm), 18-24 Months (22#: Foot Length/insole Length: 13.5 cm/14.0 cm), 2-2.5 Years (23#: Foot Length/insole Length: 14.0 cm/14.5 cm), 2.5-3 Years(24#: Foot Length/insole Length: 14.5 cm/15.0 cm), 3-3.5 Years(25#: Foot Length/insole Length: 15.0 cm/15.5 cm), 3.5-4 Years(26#: Foot Length/insole Length: 15.5 cm/16.0 cm), 4-4.5 Years(27#: Foot Length/insole Length: 16.0 cm/16.5 cm), 4.5-5 Years(28#: Foot Length/insole Length: 16.5 cm/17.0 cm), 5-5.5 Years(29#: Foot Length/insole Length: 17.0 cm/17.5 cm), 5.5-6 Years(30#: Foot Length/insole Length: 17.5 cm/18.0 cm)