X-SMALL: 52 CM / 20.47 - 20.87" / HAT SIZE: 6 1/2 - 6 5/8
SMALL: 54 CM / 21.26 - 21.65" / HAT SIZE: 6 3/4 - 6 7/8
MEDIUM: 56 CM / 22.05 - 22.44" / HAT SIZE: 7 - 7 1/8
LARGE: 58 CM / 20.84" + / HAT SIZE: 7 1/4 +
Step 1: Measure
Using a flexible fabric measuring tape, measure the circumference of your head one inch above your eyebrows. You can totally do this yourself, or you can recruit a friend to make sure the tape stays flat and even around your head for an accurate measurement. Here is our biggest suggestion...use centimeters. Your measurement in centimeters will correspond to the size of the helmet the best. I mean, we know we aren't the best at guessing what exactly a 5/8th measurement is!
Step 2: Prepare the Helmet
Before trying it on, let the chin strap out far enough so that you will be able to buckle it, and then tighten it once you have the helmet on.
Step 3: Position the Helmet
Place the helmet on your head. If it is wobbly or uncomfortably tight, try a new size. Buckle the chin strap. Make sure the helmet isn't tilted. The brim should be about an inch above your eyebrows and level across. You should feel even pressure around the circumference of your head. The chin strap should not be loose at all, but not so tight that you cannot move your head up and down comfortably.
Step 4: Check the Fit
Shake your head side to side and up and down. Your helmet shouldn't move all over the world the second it is on your head. It should be snug, but comfortable.