How Should a Motorcycle Helmet Fit? (Sizing Guide and Charts)


It is vitally important you get the sizing right when buying a new helmet.

A lid that doesn’t fit is not only annoying and uncomfortable but also dangerous.

For the best protection in an accident, follow our guide below to get the proper motorcycle helmet sizing. 

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How to measure For a helmet

First things first, you need to measure your noggin!

Use a tailors tape measure (the soft one) and measure your head at its widest point. For most people, this will be around the forehead and around the back of the head; the measure should be above the eyebrows and ears.

The images below should give you a good idea.

measuring head

Trying the helmet on

Different brands have different sizing (see charts below), so every helmet will be slightly different, try your new lid on and make sure it is tight but comfortable.

Remember, the helmet will “bed in” over the first few months, and the inner pads will compress to the shape of your head, so allow for this when testing the fit.

How snug should the helmet be?

The helmet needs to be very snug fitting; it should feel tight but not to the point of being painful.

Put the helmet on and fasten the strap, go round the helmet and check:

  • Cheek pads: You should be able to feel the cheek pads pressing against your cheeks; there should not be any gaps and no room to get your fingers in
  • Temples\forehead: Snug fitting with no room to get your fingers in
  • Back of helmet: Should be snug up to the back of the skull
  • Eyes: Your eyes should be in a central position in the visor area; if the helmet is nearer your eyebrows, it is too big. If it is too high on the forehead, it is too small.
  • Twist and rotate: The helmet should have minimal rotation when twisted 
  • Back and forth: Try pushing the helmet back and forth; it should not come off or expose any part of the head. Again you are looking for minimal movement. 

Standard helmet sizes chart

These are the standard sizes, although some brands are slightly different and are noted below. 

Head Measurement (cm's)Helmet Size
51 - 52XX-Small
53 - 54X-Small
55 - 56Small
57 - 58Medium
59 - 60Large
61 - 62X-Large
63 - 64XX-Large

Schuberth helmet size chart

Schuberth has different sizing to the above across the range.

Head Measurement (cm's)Helmet Size
52 - 53X-Small
54 - 55Small
56 - 57Medium
58 - 59Large
60 - 61X-Large
62 - 63XX-Large
64 -65XXX - Large



AGV sizing is mostly consistent with standard sizing, but some models are slightly different. See here for chart.


Sizing changes depending on the model. See here for info.

SHARP Testing

You should check the SHARP safety rating before buying a helmet. This is a government agency that provides information about the relative safety of helmets.

Further Reading

Check out our helmet reviews and round-ups to find your next lid.