*These charts are for reference only. Fit may vary depending on the construction, materials and manufacturer.
| US | CM |
| Infant US 1.5 | 9.7cm |
| Infant US 2 | 10cm |
| Infant US 2.5 | 10.7cm |
| Infant US 3 | 11.3cm |
| Toddler US 3.5 | 11.9cm |
| Toddler US 4 | 12.2cm |
| Toddler US 4.5 | 12.6cm |
| Toddler US 5 | 13.2cm |
| Toddler US 5.5 | 13.5cm |
| Toddler US 6 | 13.8cm |
| Toddler US 6.5 | 14.5cm |
| Toddler US 7 | 14.8cm |
| Toddler US 7.5 | 15.1cm |
| Toddler US 8 | 15.7cm |
| Toddler US 8.5 | 16.1cm |