Adult Helmet Size Chart
Measuring the circumference of head, just above the top of the ears and brows.
| Size | XS | SM | MD | LG | XL | 2XL | 3XL | 4XL |
|---|---|---|---|---|---|---|---|---|
| US Hat Sizes | 6 5⁄8 - 6 3⁄4 | 6 7⁄8 - 7 | 7 1⁄8 - 7 1⁄4 | 7 3⁄8 - 7 1⁄2 | 7 5⁄8 - 7 3⁄4 | 7 7⁄8 | 8 - 8 1⁄8 | 8 1⁄4 |
| Inches | 20 7⁄8 - 21 1⁄4 | 21 5⁄8 - 22 | 22 3⁄8 - 22 3⁄4 | 23 1⁄8 - 23 1⁄2 | 23 7⁄8 - 24 1⁄4 | 24 5⁄8 | 25 - 25 3⁄8 | 25 3⁄4 |
| Centimeters | 53 - 54 | 55 - 56 | 57 - 58 | 59 - 60 | 61 - 62 | 63 | 64 - 65 | 66 |