Arai Size Chart

Note: The sizing chart listed below represents the manufacturer's suggested sizing guidelines only, and is subject to change without notice. MotorcycleCloseouts is not responsible for the accuracy of any sizing charts. If you have a specific sizing question, please email us at

General Sizing Information

After many years of listening to rider feedback, we have found that satisfaction with a helmet - any helmet - starts with your understanding the importance of fit. Most importantly, understanding how proper size and fit affect how a helmet performs during every day riding, and how uninformed purchasing decisions can affect that performance.

1. MEASURING: Have someone measure the circumference of your head with a cloth measuring tape - available cheaply at any fabric store - taking special care to measure at the largest circumference (i.e. where your head is biggest; typically at just above the eyebrows, around the head to include the largest "bump" at the back of your head.) The tape must be pulled tight, and the measurement taken.

2. SNUG VS. LOOSE: A helmet that slips on easily may offer an initial impression of comfort and proper fit, but after time can become too loose and move around on your head, allowing more wind noise to get in and also causing more discomfort and fatigue as you struggle to keep your head from getting buffeted in the wind. Like a properly-fit pair of shoes, a helmet needs to settle in over time, so be sure to consider this "relaxing" of the interior when buying your new helmet. Your initial fitting goal, then, should be for a snug fit.

3. FACIAL FIT: This is a common problem with riders who have a full face, jaw, or cheeks because it often results in the mistake of "fitting your face" instead of your head, and choosing a larger size in order to get the helmet on past your face. The problem is compounded again because in a mail-order/Internet purchase there is no in-person helmet fitter to help.

Remember, first get your correct head size (Step #1). You’ll yell and scream the measured-size will never fit, but respectfully, we’ve heard that before. When you order your helmet, consider ordering one of Arai’s optional thinner-cheekpad sets for your model. Swap the pads to the thinner ones. Bingo!

4. SIZE COMPARISONS: The helmet size you’re wearing now doesn’t count in ordering a new helmet. A previous or current helmet in the same brand, model and size - even if an Arai - may not offer the same fit as a current model or size you’re considering. Why? The natural evolution of design and the use of new materials can affect - and alter - the size and fit of a new model.

Arai offers several interior shapes to give you the most possible opportunities to find one that best fits your head shape. How can you determine which is best suited for you? In general, Arai interiors for the North American markets are based on an oval shape orientation (somewhat longer front-to-back and a little narrow from side-to-side). Our models then vary slightly based on that general Oval shape to accommodate a much wider fit range.

LONG OVAL (very long front-to-back, very narrow side-to-side). On this end of the scale, we have the new Profile model, offering additional forehead room for those who find that most helmets have pressure points in the forehead.

INTERMEDIATE OVAL (a little shorter front-to-back and a little wider side-to-side). This next fit package comes in our RX-7 CORSAIR, Astral-X and Vector models, which begins the shift from oblong towards round. However, because the RX-7 CORSAIR has a fully removable liner and the Astral-X and Vector have a non-removable head liner (removable cheek pads), side-by-side fit comparisons can reveal a personal preference for one over the other.

ROUND OVAL (even a little shorter front-to-back and a little wider side-to-side). This last fit package is our popular Quantum-2 model.

No one pays more attention than Arai to the subtle variations and the infinite possibilities of the human head shape. And, even though we know we can never build a perfect shape for everyone, we make a genuine effort to offer shapes that allow more people to find a better and more comfortable fit - which we think is much better for the rider’s comfort than trying to shove everybody’s head into a single interior shape!

Arai Helmet Sizing

Manufacturer's Suggested Size Chart (Not a guarantee of fit) 
Size Centimeters 
3XS 49 - 50
2XS 51 - 52
XS 53 - 54
SM 55 - 56
MD 57 - 58
LG 59 - 60
XL 61 - 62
2XL 63 - 64
3XL 65 - 66

Arai Interior Cheek Pad Thickness Cross-Reference

Manufacturer's Suggested Size Chart (Not a guarantee of fit) 
Current size applications for non-Snell 2010. However, note that changes and updates can affect the standard pad-thickness supplied with your helmet.
Helmet Cheek pads
Size Corsair V RX-Q Vector-2 Signet Q VX-Pro 3 XC/XC Ram XD 3/XD 4
Optional  40mm - - - - - -
Optional  40mm - - 40mm 35mm - 35mm
3XS  - - - - - - -
2XS  - - 35mm - - - -
XS Std  30mm  30mm 30mm 30mm 25mm 25mm 25mm
SM Std  30mm  30mm 30mm 30mm 25mm 25mm 25mm
MD Std  30mm  30mm 30mm 30mm 25mm 30mm 25mm
LG Std  25mm  25mm 25mm 25mm 20mm 25mm 20mm
XL Std  25mm  25mm 25mm 25mm 20mm 25mm 20mm
2XL Std  25mm  25mm 25mm 20mm 20mm 25mm 20mm
3XL Std  20mm  20mm 20mm - - - -
Optional  15mm - - 15mm 12mm - 12mm
Optional  12mm - - 12mm - - -
Shell  I/O - - L/O  - - -

Shop Now
Ready to Start Shopping? Click to View/Buy Arai Gear.

Additional Questions? Contact Us for further information.