KBC Helmet Fitment Chart
To measure your correct helmet size, measure the circumference of your head, like a headband, one inch above the eyebrows, above the ears.  Match inch measurement to chart.  If between sizes, choose the next larger size. Helmet should fit snugly but not overly tight.
 
Inch Around
cm
Hat Size
KBC
19-3/4" - 20-1/8" 50-52 6-1/4 - 6-1/2 Childs S/M
21-1/4" 53-54 6-5/8 - 6-3/4 Childs L/XL
21-1/8" 51-52 6-3/8 - 6-1/2 XX-Small
21-1/4" 53-54 6-5/8 - 6-3/4 X-Small
21-5/8" 55-56 6-7/8 - 7 Small
22-3/8" 57-58 7-1/8 - 7-1/4 Medium
23-1/8" 59-60 7-3/8 - 7-1/2 Large
23-1/2" 61-62 7-5/8 - 7-3/4 X-Large
24-1/4" 63-64 7-7/8 - 8 XX-Large
24-5/8" 65-66 8-3/8 - 8-1/2 XXX-Large