Bike Helmet Size Chart – (Most Major Brands)


How many times have you gone to try on a new helmet, knowing full well that you’ve always worn an M, or Medium size, only to find that the new helmet doesn’t fit your head comfortably? What happened? Did your head just suddenly get bigger, or smaller?

No, don’t worry, your head hasn’t suddenly grown or shrunk.

The problem is that different helmet manufacturers have different ideas of what size should equate to what in terms of inches or centimeters, or even hat size. Even Universal one-size-fits-all sizes can be different from one manufacturer to another.

One brand will have a Medium size being the equivalent to 54 – 58 cm, while another brand will show Medium size as being 55 – 60 cm.

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Oh, and just to add further confusion to the confusion, US hat sizes are different from European hat sizes. [:shrug: go figure]

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The Correct Size Helmet Is Most Important

There is more to head protection than just wearing a helmet.

To protect your head properly, the helmet must fit properly, and the only way to do that is to buy the correct size helmet for your head. In order to purchase the correct size helmet for YOU, you need to know two things:
1) Your head measurement, and
2) How your head measurement relates to the brand of helmet that you plan to buy.

(For example, a Medium-sized Bell helmet is not the same measurement as a Medium-sized Kask helmet).

So, first things first, if you haven’t already, you should head over to our article called ‘How to Know Your Helmet Size’ and measure your noggin. You can do that yourself, but it’s so much easier if you have someone to help you to hold the tape measure.

After you’ve measured your head size, then you should do it again just to be 100% sure. Don’t forget, “the helmet must fit properly, and the only way to do that is to buy the correct size helmet for your head”. So, be absolutely certain that you have the correct measurement.

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Next, or as soon as you’ve decided which helmet you’re going to buy, follow the appropriate link below to the helmet brand that you plan to buy, and take note of whether that means Medium, Large, Small, or whatever size/nomenclature that the manufacturer uses to describe their sizes.

Finally, once you have the correct size helmet, follow the link below to How To Know Your Helmet Size to see how to make the necessary fitting adjustments and how to use padding to customize the fit to suit your head size and shape.

IMPORTANT: How To Know Your Helmet Size

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The links below will open the relevant Size Chart in a new Window.

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