Size Charts
Helmet Sizing
Charts
Measure once, ride right. Find your brand below for its full size range in centimeters and inches, plus how to measure your head correctly.
How to measure your head
You only need a soft cloth tape measure (or a piece of string and a ruler) and about a minute.
- Wrap the tape around the widest part of your head — roughly one inch (2.5 cm) above your eyebrows and around the back where your head is largest.
- Keep the tape level all the way around, snug but not tight.
- Measure twice and use the larger of the two numbers.
- Match it to the brand's chart above. If you fall between two sizes, size down for a snug all-day fit — the padding breaks in.
How a helmet should fit
A new helmet should feel snug, not painful. The interior padding compresses and breaks in by roughly 15–20% during the first few rides, so the right helmet is firm out of the box.
- Even all around. The cheek pads should touch your cheeks and gently push them up — you'll look a little like a chipmunk at first.
- No pressure points. Hot spots on your forehead, temples, or crown after a few minutes mean it's too small or the wrong head shape.
- No movement. Fasten the strap, grab the chin bar, and try to rotate the helmet — your skin should move with it, not slide underneath it.
- Roll-off test. With the strap fastened, try to roll the helmet forward off your head. A properly sized helmet won't come off.
- No gaps. You shouldn't be able to fit more than a finger between your forehead and the liner.
Understanding head shapes
Two riders can measure the same circumference and still need different helmets, because heads are shaped differently. Most helmets are built around one of three shapes:
- Round Oval — front-to-back and side-to-side measurements are nearly equal. Arai tends to suit rounder heads well.
- Intermediate Oval — slightly longer front-to-back than side-to-side. This is the most common shape, and most helmets (HJC, Shoei, Bell, Scorpion, Icon) are designed around it.
- Long Oval — noticeably longer front-to-back than side-to-side.
If a helmet is the right circumference but pinches your forehead and the back of your head with gaps at the sides, you likely need a longer-oval shape. If it pinches the sides with gaps front and back, you need a rounder shape.
Quick fit tips
- Between two sizes? Go with the smaller one — most padding breaks in, and many helmets offer thinner cheek pads if you need to relieve pressure.
- Wear glasses? Look for helmets with eyeglass-friendly channels in the liner.
- Tight on the cheeks but fine on the crown? That's normal — give it a few rides before judging.
- Replace your helmet roughly every five years, or immediately after any impact.
Frequently asked questions
How do I measure my head for a helmet?
Wrap a soft tape measure around the widest part of your head — about one inch above your eyebrows and around the back. Keep it level, measure twice, and use the larger number, then match it to your brand's chart above.
Should a motorcycle helmet be tight?
Yes — a new helmet should feel snug but not painful. The cheek pads should press your cheeks with no gaps at the forehead. The liner breaks in about 15–20%, so a helmet that's loose out of the box will be too big once it settles.
What if I'm between two sizes?
Choose the smaller size. Helmet padding compresses with use, and many helmets offer thinner cheek pads if you need to relieve pressure. A helmet that's too big can shift or come off in a crash.
Do helmet sizes differ between brands?
Yes. Each brand designs its own shell shape and liner, so a Medium in one brand may not match a Medium in another. Always use the specific brand's chart above, and consider its typical head shape — round, intermediate, or long oval.
How do I know if my helmet is too big or too small?
Too small: hot spots or pain on your forehead, temples, or crown within a few minutes. Too big: it shifts when you shake your head, lifts at the front, or you can fit more than a finger between your forehead and the liner. A correct fit moves your skin with the helmet and won't roll off when fastened.
Will a new helmet break in?
Yes. The comfort liner and cheek pads compress roughly 15–20% over the first several hours of use, so a properly fitted new helmet feels firm at first and loosens slightly as it conforms to your head.
All charts list head circumference in centimeters and inches. Sizing is a guide — when between sizes, riders typically size down for a snug all-day fit. © The Helmet Shop