IKKS Baby sizes 3 - 24 month
| Approximate age | Child's height | Child's chest (around) | Child's waist (around) |
|---|---|---|---|
| 3 month | 60 cm | 39.5 cm | 40.5 cm |
| 6 month | 67 cm | 43 cm | 44 cm |
| 12 month | 74 cm | 46.5 cm | 46 cm |
| 18 month | 80 cm | 49 cm | 48 cm |
| 24 month | 86 cm | 52 cm | 49 cm |
IKKS Junior sizes 2 - 14 year
| Approximate age | Child's height |
|---|---|
| 2 year | 86 cm |
| 3 year | 94 cm |
| 4 year | 102 cm |
| 5 year | 108 cm |
| 6 year | 114 cm |
| 8 year | 126 cm |
| 10 year | 138 cm |
| 12 year | 150 cm |
| 14 year | 156 cm |
IKKS pre-walker shoe sizes
 EU |  UK |  USA | Approximate age |
|---|---|---|---|
| 15-16 | 0-1 | 1-2 | 1-3 month |
| 17-18 | 1-2 | 2-3 | 3-6 month |
| 19-20 | 2-3 | 3-4 | 6-12 month |