| Size | Head Circumference | Hat Size | Metric Size |
|---|---|---|---|
| XX-Small | 19.68 - 20 | 6 3/8 | 50 to 51 |
| X-Small | 20.47 - 20.87 | 6 5/8 | 52 to 53 |
| Small | 21.26 - 21.65 | 6 7/8 | 54 to 55 |
| Medium | 22.05 - 22.44 | 7 1/8 | 56 to 57 |
| Large | 22.83 - 23.23 | 7 3/8 | 58 to 59 |
| X-Large | 23.62 - 24.02 | 7 5/8 | 60 to 61 |
| XX-Large | 24.41 - 24.80 | 7 7/8 | 62 to 63 |
| XXX-Large | 25.20 - 25.59 | 8 1/8 | 64 to 65 |