Adult Helmet Size Chart

ADULT HELMET

SIZE HEAD CIRCUMFERENCE
INCH CM
2XS 20 - 20 ½ 51 - 52
XS 20 7⁄8 - 21 ¼ 53 - 54
S 21 5⁄8 - 22 55 - 56
M 22 ½ - 22 7⁄8 57 - 58
L 23 ¼ - 23 5⁄8 59 - 60
XL 24 - 24 3⁄8 61 - 62
2XL 24 ¾ - 25 ¼ 63 - 64
3XL 25 ¼ - 25 3⁄8 64 - 65
4XL 25 3⁄8 - 26 65 - 66
Measure the circumference of your head, one inch above the eyebrows and the ears, then refer to the chart.