Giro, Atomic, and K2 Helmet Sizing Chart

Determining your helmet size.

Use a soft measure tape for best results.
Measure around your head, just above the eyebrows staying parallel to the floor.
If you wear a headliner, measure with it on.
If you're between sizes, go to the larger size.

SIZES	Giro Kid's Helmets	Giro Adult Helmets	Atomic Helmets	K2 Helmets	Salomon Helmets
XS / SM Kids	49 - 52cm 19.25 - 20.5 in.
MD / LG Kids	55 - 55.5cm 20.5 - 21.75 in.
SMALL		52 - 55.5 cm 20.5 - 21.75 in.	53 - 56 cm 21.25 - 22.75 in.	51 - 55 cm 20 - 22.5 in.	53 - 56 cm 21.75 - 23.25 in.
MEDIUM		55.5 - 59 cm 21.75 - 23 in.	56 -59 cm 22.75 - 23.25 in.	55 - 59 cm 22.5 - 23.25 in.	56 - 59 cm 22.75 - 23.25 in.
LARGE		59 - 62.5 23 - 24.25 in.	59 - 62 cm 23.25 - 24.25 in.	58 - 61 cm 23 - 24 in.	59 - 62 cm 23.25 - 24.25 in.
EXTRA LARGE		62.5 - 65 cm 24.5 - 25.5 in.		58 - 61 cm 23 - 24 in.