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Helmets for Large Heads

Summary: There are some helmets on the market that fit larger heads. And if they seem to perch on top of your head, we have some ideas for that problem.

Some riders need extra extra large helmets. That includes some with medical conditions that result in very large head sizes, and some who just have naturally large heads. Here are the largest models we know of, although this page is due for a major revision, and a number of them may no longer be available:

  • Atlas X-treme M3 Extra from Asctechs: 68cm heads (US size 8 1/2, 26-3/8 inches) No standard certification listed, so may not be a bicycle helmet.
  • Bontrager Quantum: fits up to 26.0"/66cm heads.
  • Fly Racing BMX/motorcycle models: Trophy II, Gmax GMX-46X, Gmax GMX-46Y, fit up to 26.0"/66cm heads.
  • Prowell Lightning: reported by one emailer as fitting his 66cm head.
  • Bell Stoker: fits heads up to 25.6/65cm. Replaces the Kinghead.
  • Bell XLV: fits heads up to 25.6/65cm.
  • Bell XLP: fits heads up to 25.6/65cm.
  • Bell Traverse XL: fits heads up to 25.5/65cm.
  • Bern Brentwood: fits heads up to 25"/63.5cm
  • Bern Macon: fits heads up to 25"/63.5cm
  • Cratoni C-Stream: fits up to 25.6/65cm heads. (rounder interior)
  • Giro Chronicle XL: a 2019 model. See this review.
  • Giro Register aka Giro Bronte: fits up to 25.6/65cm heads.
  • Louis Garneau Quartz: fits up to 25.6/65cm heads.
  • Uvex X-Ride/X-Fit: fits up to 65 cm (25.6 inch) heads. Can be ordered from Wheelfine Imports. <>I>Lazer Vandal: fits up to 25.2"/65cm heads.
  • Catlike Tako: fits up to 25.2"/64cm heads.
  • Kask Mojito XL: fits up to 25.2"/64cm heads. Asian head shape.
  • LAS Big Devil: fits up to 25.2"/64cm heads.
  • Etto Vortex: fits up to 25.2"/64cm heads.
  • Specialized Max Adult XXL: advertised at 64cm (25.2), but fits some who found the Bell helmets listed above were too small.
  • Vigor NOX: fits up to 25.6"/65cm heads.
  • Giro Atlas II: fits up to 24.8"/63cm heads.
  • Giro Radix MIPS XL: fits some wider heads better than the Specialized Max XXL.
  • Ked City: fits up to "64cm +" (25.2" +) heads.
  • Ked Neo Visor: fits up to 64cm (25.2 inch) heads.
  • Limar Big One: fits up to 24.8"/63cm heads.
  • Louis Garneau Olympus and Arcterus: fit up to 24.8"/63cm heads, but some emailers tell us that Garneau's larger sizes fit them better than others. One who has a large Asian head with a rounder profile found that the Arcterus fit him well. Another with an oblong head said the same thing.
  • Netti Quantum Pro: fits up to 24.8"/63cm heads.
  • Nutcase L: Skate style helmet, L/XL advertised as 64cm. A shop specializing in large bikes for large people informs us that the Nutcase in L/XL fits many customers who have larger heads. That has been confirmed by individual emails.
  • Nutcase XL: Skate-style helmet that fits some heads larger than its advertised size.
  • S1 Lifer: Skate-style helmet that fits 25.5-inch heads and with the 4mm sizing inserts removed can accommodate 25.75 inches. S1 is working on large sizes and round head accommodation.

You can find comments on each of these helmets in our Helmets for the Current Season article.

Many tape measures are not accurate. Measuring your head is not very precise, either, so the numbers above should not be taken as exact. We have a sizing page for converting fraction/inch/cm sizes.

Success in fitting a large head depends on the shape as well as the size. Some emailers report that they can use a smaller size with some helmets due to the shape, or that one helmet with the same measurements has more room for them than another. That depends on the individual head shape and the interior profile used by the manufacturer, both difficult for us to pin down and best determined by a fitting. We do note that the Cratoni Radon seems to work better for rounder heads. We have more on that on our page about helmets for rounder heads. That can also mean more room for a wider head. For longer, narrower heads we have received good comments about the Bontrager Quantum, some from riders who have tried many other helmets.

You may have already tried one of these helmets, and of course you have already tried removing most or all of the foam fitting pads. That is the only way to make more room for your head without modifying the helmet in a way that reduces protection.

Perched on top of your head?

If most helmets seem to perch on top of your head, leaving the sides uncovered, there are some options. First you can take out the fitting pads in the top to move the helmet further down. You can also use a larger helmet with more headroom, putting thicker fitting pads on the sides. If you are lucky, you can fit in one of the bike helmets with additional side coverage, like the THE F-20, Giant Realm, Fox Flux, POC Trabec, Pro-Tec Cyphon and SixSixOne Recon. See our page on helmets for the current season for more info on them. Or if you can stand the lack of ventilation, one of the skate-style helmets noted in the list above may work for you.


This disorder results in very large heads. Unfortunately, we do not know of any manufacturer who makes helmets to respond to this need. An extensive search by a Florida hospital in the fall of 2016 failed to find a source for a bike helmet for hydrocephalitic heads.

Custom Helmet?

We do not know of any manufacturer now producing extra large custom helmets. The tooling to do that would be expensive, and they would have to produce extras for the lab testing to certify the helmet as a new model. As new liner materials become available it may become more practical to produce a custom helmet, but the extra large outer shell would still be a problem, and the certification testing would still be required.

And the future: Register your needs

Over the decades, the average American's head size has increased. Manufacturers are aware of this long term trend, but until the 2005 model year they apparently doubted that there was a large enough market for extra large helmets to make a profit on them. Up until then, only Bell had produced an XXL model, fitting up to 8 1/4 or 26" circumference heads. In the years since then, more manufacturers are making larger sizes, but still not large enough for some heads.

If demand becomes more evident, more large helmets will appear on the market. We have tried to help by highlighting this need to helmet manufacturers at ASTM helmet standards committee meetings and suggesting to the manufacturers that there might be money to be made making a larger helmet. It could help if more people needing large helmets would contact the manufacturers. Here are a few selling in the US market:



Louis Garneau





And at least one in Japan, made for rounder heads, the OGK Kabuto Steair-X. See our page on rounder heads.

Please let us know with an email if you find other good solutions to this problem that we can pass on to the next person with a very large head, or if you find a helmet that works particularly well with your head shape.

Here is our page on helmets for very small heads.

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This page was revised on: February 3, 2022. BHSI logo