Helmet Sizing Chart
Average Head Circumference by Age
| AGE | Head Size - Girl (cm) | Head Size - Boy (cm) | Our Sizes (cm) |
| 1 year | 45 | 46 | ABUS S: 45-50 |
| 2 years | 47 | 48 | Micro S: 48-53 |
| 3 years | 49 | 49 |
ABUS YouDrop S/M: 48-55 |
| 4 years | 49.5 | 50.5 |
Aero S: 50-54 |
| 5 years | 50 | 51 | |
| 6 years | 51 | 52 |
ABUS M: 50-55 |
| 7 years | 52 | 53 |
Micro M: 52-56 |
| 8 years | 53 | 54 |
Micro L: 58-61 |