Giro Helmet Size Guide

SUPER FIT™ HELMET SIZE SIZE (CM) SIZE (IN)
XS 47 - 51 18.5 - 20
S 51 - 55 20 - 21.75
M 55 - 59 21.75 - 23.25
L 59 - 63 23.25 - 24.75
XL 61 - 65 24 - 25.55
*The Large Quarter Bike Helmet is the following dimensions: Large: 23.25" - 24.25" / 59 - 61.5 cm
 
UNIVERSAL FIT HELMET SIZE SIZE (CM) SIZE (IN)
CHILD 50 - 55 19.75 - 21.75
YOUTH 50 - 57 19.75 - 22.5
ADULT 54 - 61 21.25 - 24
WOMEN 50 - 57 19.75 - 22.5
XL 58 - 65 22.75 - 25.5
 
YOUTH SIZE (CM) SIZE (IN)
S/M 46 - 50 18 - 19.75
M/L 50 - 54 19.75 - 21.5
TODDLER 48 - 52 18.75 - 20.5