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A helmet is probably your most important cycling purchase. Helmets quite literally save lives so finding the right one is essential.
A well-fitted helmet should rest level on top of your head. It should be snug (but not too tight) and leave only a small portion of the forehead visible. That might sound simple enough, but getting the right helmet can be a challenge.
Helmet sizes are fairly generic (see the table below) with little accommodation made for anyone with an unusually shaped or especially large head. This can sometimes lead cyclists to give up on wearing a helmet altogether, which is extremely dangerous.
If you can’t find a helmet to fit, this guide to helmets for big heads should help you stay safe and comfortable on the road.
Extra Large Bike Helmet
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Heads sized: 60-66cm
Bontrager Quantum MIPS XL
Offers advanced safety, lightweight comfort, and MIPS technology with 22 vents for a perfect fit.
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Heads sized: 59-65cm
Cratoni C-Stream Helmet
a high-performance bike helmet that offers comfort, ventilation, and reliable protection for cyclists.
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Heads sized: 61-65cm
Bell 4Forty MIPS XL Helmet
Offers premium comfort and protection for larger head sizes with advanced MIPS technology.
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Heads sized: 50 to 62cm
Kask Mojito 3
A lightweight and stylish bike helmet that combines comfort, ventilation, and superior protection.
Bike Helmet Sizes
Bike helmets usually range from as small as 51cm (extra small) up to 63cm (extra large). As a basic rule, helmets fit according to this size chart:
| Classification | Helmet size |
|---|---|
| Extra small | under 51cm |
| Small | 51cm–55cm |
| Medium | 55cm–59cm |
| Large | 59cm–63cm |
| Extra large | above 63cm |
One size fits all helmets are a little different and come with an adjustable fit mechanism, but even these have limits at either end.
What is the Biggest Bike Helmet Size?
The biggest bike helmet that you’ll usually be able to find is 66cm. This is sometimes also called 4XLarge. Of course, specialist brands will occasionally manufacture bigger ones for larger heads.
Where to Find a Bike Helmt for Large Head
If you’re struggling to find a helmet that fits, don’t despair. Some brands specialise in extra large helmets. These include Bell, Bontrager, Giro and Cratoni. These companies offer much bigger helmets, well above the more common measurements.
Best Bike Helmets for Big Heads
| Rank | Helmet | Fits Heads Sized | |
|---|---|---|---|
| 1 | Bontrager Quantum MIPS | 60-66cm | READ REVIEW |
| 2 | Cratoni C-Stream Helmet | 59-65cm | READ REVIEW |
| 3 | Bell 4forty MIPS Helmet | 61-65cm | READ REVIEW |
| 4 | Kask Mojito 3 | 50-62cm | READ REVIEW |
1. Bontrager Quantum MIPS XL
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£85 -
$97 -
€97
Prices are approximate
Fits Heads Sized: 60 to 66cm
Weight: 335g
Easily one of the biggest helmets in the world, the Quantum fits heads up to an impressive 66cm. You won’t find many helmets bigger than that, making it the perfect choice if you’ve been struggling for a long time. Bontrager market this helmet as offering “everything you need and nothing that you don’t”, so the emphasis is on safety and comfort.
MIPS (Multi-directional Impact Protection System) was developed alongside brain surgeons to reduce rotational forces acting on the brain after an angled impact. A tough, composite skeleton increases the helmet’s structural integrity and provides virtually unparalleled protection. The Crash Replacement Guarantee means a new helmet if you’re involved in a collision in the first year.
All that protection doesn’t come at the expense of comfort, though. The padding is soft and luxurious, while internal channels move air across your head, keeping you cool and preventing sweat build up. It also comes with a snap on visor, useful in sunnier weather but easily removed if not required.
Some helmets (especially larger ones) can be fiddly, but Bontrager has you covered here, too. The fit system is smooth and you can easily slip the helmet on and off/adjust it using just one hand.
2. Cratoni C-Stream Helmet
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£55
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$63
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€63
Prices are approximate
Fits Heads Sized: 59 to 65cm
Weight: 280g
The XXL version of Cratoni’s C-Stream is a massive, chunky helmet. Clocking in at up to 65cm it should fit even the largest of heads! Cratoni specifically markets this helmet for big heads, promising “optimal fit” no matter your size. It’s certainly comfortable, with no less than 14 ventilation openings and Clean Tex pads treated to prevent the formation of bacteria.
Safety is obviously paramount, and Cratoni has you covered. EPS material is foamed directly into the polycarbonate shell of the helmet, offering superior impact protection without compromising on comfort. There’s also a built in rear light (that can be turned on with a single click). The light is simple to operate and makes transitioning from day to night cycling as easy as the touch of a button.
Despite its stocky appearance, the C-Stream isn’t the heaviest on the list at 280g. Special RLS (Rapid Lock System) technology allows you to adjust the helmet via a rotating wheel on the back – this only requires one hand, so it’s perfect when you’re on the move. It even comes with insect protection at the front so you won’t have to worry about bugs ruining your ride! More than just an extra large helmet, the C-Stream is also extra safe and extra comfortable.
3. Bell 4Forty MIPS XL Helmet
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£99
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$110
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€105
Prices are approximate
Fits Heads Sized: 61 to 65cm
Weight: 380g
The Bell 4Forty MIPS helmets is one of the most stylish pieces out there. Its slick, streamlined design has a futuristic and unhindered look, and webbing around the air vents gives it an even cooler aesthetic. With a range of features suitable for every kind of ride, this is the quintessential “all rounder” helmet.
It has a tough, polycarbonate shell and MIPS offers additional protection against the most dangerous, angled impacts. A simple button and dial setup allow for easy size and adjustment on the move without having to stop: it’s fully one handed. Weighing in at 380 grams this is a mid range helmet in terms of weight.
Multiple vents will help you keep cool and there’s a removable visor too. You’ll struggle to find any helmets bigger than this, or many that offer better value for money. It’s the cheapest on the list but doesn’t skimp on protection or quality (it features that all important MIPS, something that you should look for on any helmet). 4XL is the biggest available but you can also opt for 3XL or 2XL, which are still bigger than most other helmets on the market!
4. Kask Mojito 3
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£139
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$160
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€160
Prices are approximate
Fits Heads Sized: 50 to 62cm
Weight: 230g
The Mojito 3 fits heads up to 62cm and it’s loaded with futuristic features that make it stand out in the crowded helmet market. All of this comes at a cost, however. This is the most expensive helmet on the list by a considerable distance. Still, helmets are a long term investment and you certainly get your money’s worth with this one.
The helmet surpasses European safety standards by 48% with big improvements in front, top and rear impact areas. It passes the Rotational Impact WG11 Test (which looks at how helmets perform during rotational impacts – the most dangerous kind). Better still, the OctoFit retention ensures a perfect fit, making the helmet even safer.
Padding is generous, comfortable and well ventilated. There are plenty of high visibility colours available including yellow, orange and red to help you stand out on even the darkest night. The price tag might be a bit much for some, but if you’re willing to make the investment, this is one of the safest helmets on the market. It’s one of the most comfortable too, and unlike other large helmets, it has a snug feel, making it ideal for any kind of ride from the daily commute to something more extreme.
