iOutdoor Bike Helmet Size Chart





iOutdoor Bike Helmets Standard Sizing

Model S M L
Multi-Sports Safety Helmet 48 – 54cm 55 – 57cm 58 – 61cm
18.9″ – 21.2″ 21.3″ – 22.4″ 22.5″ – 24″
Kids Bike Helmet 48 – 54cm 55 – 57cm 58 – 61cm
18.9″ – 21.2″ 21.3″ – 22.4″ 22.5″ – 24″

iOutdoor Bike Helmets Universal Sizing

Model Universal Size
Lightweight Adult Bike Helmet 56 – 64cm
22″ – 25¼”