Size Charts for Bern Water Helmets
Adult
| US Size | Centimeters | Inches |
| X-Small | 52 - 53 1/2 | 20 1/2 - 21 |
| Small | 54 - 55 1/2 | 21 - 21 7/8 |
| Medium | 55 1/2 - 57 | 21 7/8 - 22 1/2 |
| Large | 57 - 59 | 22 1/2 - 23 1/4 |
| X-Large | 59 - 60 1/2 | 23 1/4 - 23 7/8 |
| XX-Large | 60 1/2 - 62 | 23 7/8 - 24 3/8 |
| XXX-Large | 62 - 63 1/2 | 24 3/8 - 25 |
Kids - Nino and Nina Models
| US Size | Centimeters | Inches |
| X-Small / Small | 48 - 51 1/2 | 18 7/8 - 20 1/4 |
| Small / Medium | 51 1/2 - 54 1/2 | 20 1/4 - 21 1/2 |