Arai Helmet Size Conversion Chart

This chart shows the helmet size conversion guide that Arai helmets use. This will allow you to measure your head and identify what size Arai helmet that you’ll need for the best fit.

ARAI HELMET SIZE CONVERSION CHART
 Inches  Hat Size Metric Equals
 21-1/4 6-3/4 54 Small
 21-5/8 6-7/8 55 Small
 22 7 56 Medium
 22-3/8 7-1/8 57 Medium
 22-3/4 7-1/4 58 Large
23-1/8 7-3/8 59 Large
23-1/2 7-1/2 60 X-Large
 23-7/8 7-5/8 61 X-Large
 24-1/4 7-3/4 62 XX-Large