If you're overwhelmed by all the bike helmet options out there today, you're not alone. But the good news is narrowing down the options to find your perfect helmet isn't as hard as it seems. Here's everything you need to know to make the right choice on your next helmet, no matter how and where you like to ride.
Why wear a bike helmet?
Helmets are important for every rider and every ride, because they're designed to protect your most valuable asset: your brain. Modern helmets have changed a lot in the recent past. Today, they're built with features that make them more comfortable and aerodynamic, and some helmets are designed to help address linear and rotational energy.
Though no safety gear can protect you from every scenario, helmets today have been designed to protect your head from certain accidents.
How do bike helmets work?
Cycling helmets typically have a thin shell on the outside, thick foam inside and straps to help keep the helmet in place during normal use and in the event of a crash.
The foam inside is designed to crush and crack on impact, cushioning the blow and dispersing the force of the impact. The shell is designed to keep the foam together in the event of an impact. Some helmets also have a structural cage inside the foam to help the foam keep its shape. And the straps keep the helmet on your head, so it’s important that they’re adjusted properly.
What size helmet do I need?
Choosing the correct helmet size, and then adjusting it so it fits properly is important to proper helmet function. Helmet manufacturers offer several size options and different types of fit systems to help you find your perfect fit. We've included the Bontrager helmet sizing chart below as an example. If you are unsure if you have the right fit, visit your closest Trek retailer or local bike shop for assistance.
Learn more about helmet fit and sizing
| Headform shape | Helmet size | Fit range (cm) | 46 | 47 | 48 | 49 | 50 | 51 | 52 | 53 | 54 | 55 | 56 | 57 | 58 | 59 | 60 | 61 | 62 | 63 | 64 | 65 | 66 |
| STANDARD | Toddler | 46-50 | Toddler | ||||||||||||||||||||
| Child | 48-52 | Child | |||||||||||||||||||||
| Youth/XS | 50-55 | Youth/XS | |||||||||||||||||||||
| Small | 51-57 | Small | |||||||||||||||||||||
| S/M | 51-58 | S/M | |||||||||||||||||||||
| Medium | 54-60 | Medium | |||||||||||||||||||||
| M/L | 55-61 | M/L | |||||||||||||||||||||
| Large | 58-63 | Large | |||||||||||||||||||||
| X-Large | 60-66 | X-Large | |||||||||||||||||||||
| ASIA | S/M | 51-58 | S/M | ||||||||||||||||||||
| M/L | 55-61 | M/L | |||||||||||||||||||||
Bike helmet technology
Most helmets are made with EPS foam, but some are designed with both EPS and additional technologies that are designed to help mitigate certain head injuries. Two newer technologies used in Bontrager bike helmets are Mips and WaveCel.
WaveCel bike helmets
WaveCel is a collapsible cellular structure that lines the inside of the helmet. WaveCel is a revolutionary, Bontrager-exclusive helmet technology that is designed to absorb linear and rotational energy that occur during certain helmet impacts. This Bontrager-exclusive technology disrupts the safety standards that the industry has accepted for over 30 years.
Mips bike helmets
Mips stands for Multi-directional Impact Protection System. The Mips Brain Protection System (BPS) allows the head to move inside the helmet which may reduce the harmful rotational motion otherwise transferred to the brain.
EPS foam bike helmets
Expanded polystyrene (EPS) is a crushable, energy-absorbing foam used in the helmet liner, under the shell. The material is designed to help absorb linear energy when impacted.
What’s the best bike helmet for me?
In order to choose the bike helmet that's perfect for you, first consider your riding style and the terrain where you'll spend most of your time riding.
Road bike helmets
The best road bike helmets are lightweight, highly ventilated and aerodynamic to help keep riders cool and fast out on the road.
Shop road bike helmetsMountain bike helmets
High-end mountain bike helmets are light, well-ventilated and extend further down the back of the head to provide additional coverage while on the trail. They also have visors to block sun and branches on the trail.
Shop mountain bike helmetsCity and commuter bike helmets
These helmets are designed for style and functionality on city streets. They’re comfortable, versatile and ready for all sorts of two-wheeled adventures.
Shop city and commuter helmetsElectric bike helmets
E-bikes can go faster than regular bikes. E-bike riders may want to consider purchasing a bike helmet that is NTA 8776-certified and designed for e-bike use.
See Charge WaveCel helmetKids’ bike helmets
We recommend that children wear bike helmets whether they’re riding a balance bike, a big kid bike or tagging along in a trailer.
Learn moreBike helmet accessories
You can add useful accessories like sun-blocking visors and light mounts to your helmet. Use accessories that are approved for use with your helmet by the helmet’s manufacturer.
Learn moreDo bike helmets expire?
Bike helmets have a limited lifespan in use and should be replaced when they show obvious signs of wear. Additionally, helmet parts lose strength over time, so even if the helmet has not been impacted or damaged, we recommend replacing it after three years.
What should I do if I crash?
Bike helmets are designed to absorb shock by partial destruction of the shell and liner. This damage may not be visible. Therefore, if subjected to an impact, the helmet should be destroyed and replaced even if it appears undamaged.
Bontrager crash replacement warrantyCan I replace or remove the bike helmet visor?
Yes, replacement visors are easy to install and are readily available from most manufacturers. It’s also easy to remove your bike helmet visor completely if you prefer to ride without one. Some helmets even come with plugs to insert into the helmet where the visor was taken off to make it more aesthetically pleasing.
Learn more about helmet accessoriesCan I replace or clean bike helmet pads?
Yes, most bike helmet pads are removable and can be easily washed by hand. It’s also easy to find replacement pads for most helmets. If you’re unsure if your pads can be washed, consult your helmet’s manual for your manufacturer’s recommendation.
Learn how to clean your bike helmetCan I adjust the fit of my helmet?
Most helmets are easily adjustable to make the helmet more comfortable to your unique head shape. Fit systems at the rear of the helmet and straps on the sides make it easy to keep the helmet snug and in place.
Learn more about helmet fit and sizingAre bike helmets required?
Every country has its own helmet laws, and in the US, there is no federal law requiring the use of bicycle helmets. Regional laws on bicycle helmet use may vary, so consult the local rules and regulations for where you live and ride. If you are unsure where to find this information, your local bike shop is a great resource.
Why choose a Bontrager helmet?
Crash Replacement Guarantee
If your helmet is impacted within the first year of ownership, we'll provide you with a free replacement through Bontrager's Crash Replacement Guarantee. This programme is available to original owners. Contact us or your local Trek retailer with your impacted helmet, original sales receipt, details of the incident and your delivery information.
Unconditional 30-Day Guarantee
If for any reason you're not satisfied with your Bontrager helmet purchase, return the item, along with the original sales receipt to the original place of purchase within 30 days for an exchange or refund. Think of it as a 30-day test ride.
Our helmets build the future
$1 from the sale of every Bontrager helmet supports PeopleForBikes, which provides guidance, a rating system, a leadership conference and professional support for transforming cities through the globe in the ongoing effort of becoming a bicycle friendly world. [Not available in all markets]