Our team of gear gurus spent the last 6 years testing 25 of the best bike helmets and recently purchased 13 of today's top models for our latest head-to-head analysis. From the Sierra Nevada to the California Coast, we put these lids through the wringer in all kinds of weather conditions including rain, snow, wind, and beating sun. Our test rides ranged from slow, grueling mountain climbs with hair-raising descents to general training rides to casual daily commutes to the office. Protecting your brain is a no-brainer, and whether you're searching for maximum ventilation, lightweight performance, ultimate comfort, or top value, we've got you covered!
The Best Bike Helmets
Wednesday October 2, 2019
Our Editors independently research, test, and rate the best products. We only make money if you purchase a product through our links, and we never accept free products from manufacturers. Learn more
Best Overall Road Bike Helmet
Giro Synthe MIPS
Comfortable
Good ventilation
Aerodynamic and lightweight
High price tag
Some exposed foam around brim
The Giro Synthe MIPS brings home consistently high scores in nearly every evaluation metric. The Synthe MIPS takes the prize with exceptional comfort, little weight, and a low-profile shape that's semi-aerodynamic. While the Synthe isn't quite as well-ventilated as its sibling the Giro Aether MIPS, our testers prefer the fit and feel of the Synthe and didn't feel too much of a sacrifice with the ventilation. With one of the lowest weights in the lineup and a built-in MIPS liner for improved crash protection, the result is a high-performance training and racing helmet, the best of the bunch.
One potential shortfall with the Synthe MIPS is its exposed EPS foam on the lower part of the helmet brim, which could potentially be damaged if dropped or scraped against. While this weight-saving design feature is not uncommon with other models in the lineup, it just means you'll need to give your helmet a little extra care during storage and transport.
Read review: Giro Synthe MIPS
Best for Aero Road Bike Helmets
Kask Infinity
Aereodynamic design
Adjustable vents
Very comfortable
No MIPS liner
Fairly heavy
The Kask Infinity earns its spot as our top aerodynamic pick with its sleek design featuring a unique retractable door that opens up for extra ventilation or closes to provide a smooth and streamlined profile. This helmet makes an excellent choice for riders looking to do a lot of solo breaks, sprinting, and maybe an odd time trial, but don't want to completely sacrifice ventilation for improved aerodynamics. The caveat here is that while its ventilation is certainly noticeable, as an aero helmet, the ventilation performance doesn't quite stack up to that of fully adequately ventilated road helmets.
The Infinity also has a thick padding system that helps draw moisture away from the head in warmer weather and helps insulate in cooler weather. The upside is that this makes cold weather riding more comfortable with the close-able vent and roomy headcase that fits a warm cap or beanie, but the downside is that it tends to get toasty in warmer temperatures. If you tend to do most of your riding when the mercury rises, you may want to look into a better-ventilated option, which typically means giving up some aerodynamic qualities. If you are set on an aero profile but want a flexible design with reasonable ventilation, you'll have a hard time finding a better performing model, which is why the Kask Infinity earns our Top Pick Award for Aero Road Bike Helmets.
Read review: Kask Infinity
From left to right: Giro Synthe MIPS, Smith Network MIPS (previously tested), Giro Aether MIPS, Giro Foray MIPS (previously tested), Specialized Evade II ANGi, Specialized Airnet
Why You Should Trust Us
To test road bike helmets, we enlisted the help of Nick Bruckbauer and Ryan Baham. Nick likes to spend his weekends grinding away in the mountains above Santa Barbara, CA, and Ryan is an avid road east-coast road cyclist who regularly ticks off 100+ mile rides.
After selecting the top-performing products on the market, we put our lineup of helmets through the wringer. We poked, prodded, and weighed each model in our lab, and then took them out on a whole lot of bike rides through a wide variety of conditions. These helmets were subjected to sweltering heat, heavy rains, frosty spring adventures, up some grueling climbs, and down some blazing descents.
Related: How We Tested Road Bike Helmets
Analysis and Test Results
To help you determine the best road bike helmet for your needs, we purchased 13 of the highest-rated and most popular models on the market and put them through miles and miles of test rides through all sorts of conditions. While all of the helmets meet the same safety standards set by the U.S. Government, construction methods and design features vary by manufacturer and model. Below, we break down our test results and identify the top performers in each of our scoring metrics, including comfort, adjustability, weight, style, ventilation, and durability.
Related: Buying Advice for Road Bike Helmets
Most bike helmets are made from Expanded Polystyrene (EPS) foam and are intended to withstand one single significant impact, where the foam liner of the helmet is designed to crush and compress while absorbing the energy of the impact. Once a helmet is compressed, cracked, or impacted, it should be replaced because it will no longer have the same level of protection. Helmets made using Expanded Polypropylene (EPP) tend to have a more rubbery rebound with multi-impact capability, which means they can take more hits without losing their form and performance, but that means your skull might be absorbing more of the impact.
Rotational Impact Protection
Many bike helmets on the market today also come with a Multi-directional Impact Protection System (MIPS), which incorporates a thin plastic liner inside the helmet between the EPS foam and the padding that sits against the head. This layer is designed to act as a "slip-plane" between the head and the helmet, with the intention of reducing rotational forces on the brain that can result from certain types of impacts.
Of the 13 helmets in our current lineup, 10 are equipped with a built-in MIPS liner. On most models, the MIPS liner consists of the typical thin plastic slip-plane liner that is housed between the EPS foam and the padding that sits against the head. Two models we tested take the design a step further. The Giro Aether MIPS has a MIPS Spherical system that eliminates the standard plastic liner and instead consists of a two-piece dual-density foam shell where the two pieces are free to rotate against each other. The Specialized S-Works Evade has a MIPS SL system that incorporates the MIPS liner into the helmet paddings itself, rather than as a separate individual layer between the padding and the foam shell. These unique designs don't necessarily provide any additional crash protection compared to a traditional MIPS liner but are intended to improve comfort and reduce weight.
In recent years, one could expect to pay an additional 5%-10% in price and add an extra 20-30 grams weight for a MIPS-equipped helmet. We think this is certainly an acceptable price and weight penalty for the claimed additional safety benefits. Most higher-end models now come standardly equipped with a MIPS liner, and we expect to see this trend continue and the technology trickle down to most of the market. As the technology evolves, we also expect to see the designs continue to evolve and become lighter and more uniquely integrated into the helmet.Value
To help you find the best balance between price and performance in your next road bike helmet, we rated each helmet in our lineup against the competition and mapped out which models represent the best overall value. The Catlike Kompact'o Urban offers exceptional value.
Comfort
Road cyclists often spend long days in the saddle for both training and racing, making a comfortable helmet a crucial piece of equipment. Ideally, your helmet should "disappear" once you put it on and shouldn't cross your mind during your ride. While head sizes and shapes are extremely variable from rider to rider, our testers consistently found certain design features that helped a helmet adapt to different heads, adding to the overall comfort regardless of the user. In contrast, during our full-face helmet review, we found the shape of a rider's head to be much more of a factor in a particular helmet's comfort.
Our testing revealed that padding design, full circumference headband adjustability, and chinstrap design each played an essential role in overall comfort. Quality padding is crucial, especially in the forehead and temple areas, because the headband adjustment systems on most helmets tighten in the back, pushing the head against the front of the helmet. While quality padding is a critical component, we found that the location and coverage of the padding and the shape of the foam liner were more important than the thickness or density of the padding itself. For example, the Kask Protone has some of the thickest, most luxurious pads out of any helmet we tested, yet is outscored by the Giro Synthe MIPS in our comfort ratings. The Specialized S-Works Evade also strikes a nice balance of padding density and coverage, and a comfortable cradling of the head by the headband for a snug, secure fit.
The luxurious padding makes the Evade one of the most comfortable helmets we've tested.
All of the helmets we tested have internal headband systems that allow adjustment to fit various head shapes and sizes. The best designs are those that make a complete loop around the head, rather than those that do a partial loop and anchor into the helmet liner near the temples. The Catlike Kompact'o has a particularly useful side wing adjustment option to fit all sorts of interesting head shapes. The adjustment systems on the Giro Synthe MIPS, Giro Aether MIPS, and Specialized S-Works Evade also wrap entirely around the head, earning these models top scores in this category.
The comfortable padding design, full circumference headband, and adjustable Y-buckle chinstraps make the Synthe one of the most comfortable models we tested.
Chinstrap design also plays a significant role in helmet comfort. Our testers preferred helmets that incorporated thin webbing straps and a Y-buckle, allowing the straps to lie flat against one's face. The Specialized models and the Giro models use different strap designs, but models from both of these brands stand out with thin, supple webbing material and well-designed Y-buckles that allow the webbing to lie flat.
Overall, the Giro Synthe MIPS, Kask Infinity, and Specialized S-Works Evade stand out as the most comfortable models we tested. These helmets all have the best combinations of sufficient and well-placed padding, full circumference adjustable headband systems, and comfortable chinstrap systems.
The S-Works Evade has comfortable chinstraps that lay flat against the face, luxurious padding, and a full circumference adjustable headband.
Adjustability
A helmet must fit well to be comfortable and to function as designed. For a helmet to protect you, it must stay on your head. Correct fore/aft positioning, headband tightness, and chinstrap tension will help ensure that your helmet stays squarely on your head and is ready to protect you when if you ever need it.
All of the helmets in our lineup have a chinstrap system with one strap behind the ear and one in front, where the straps are joined below the ear with a plastic Y-buckle. On most helmets, the Y-buckle allows the straps to be adjusted to change the height of or the tension between the front and rear straps. Models with an adjustable Y-buckle typically scored higher in the adjustability rating metric. Despite its lack of an adjustable Y-buckle, the Specialized Airnet seems to have the ability to fit a broad range of heads while maintaining equal tension on the front and rear straps. The Kask Protone is the opposite - the lack of adjustability was a deal breaker for some testers who could not achieve equal tension on the straps. Some models have strap designs that feed through the helmet's liner to provide more side to side adjustability, while others have straps that are permanently anchored to the liner.
Each helmet has an adjustable dial near the back of the helmet to adjust the fit and the tension of the helmet's headband. The Lazer Z-1 MIPS has a unique design where the tension dial is at the top of the helmet. While he internal headband sizing varies between manufacturers, most medium-sized helmets we tested offer 4-6 cm of size adjustment and fall somewhere in the 52-60 cm size range, and most large models offer 4 cm of size adjustment and typically have a 59-63 cm size range.
The headband adjustment dial is one of the key features we tested in our adjustability ratings.
While the tension dials on every helmet function as intended, some are on the smaller side such as on the Giro Synthe MIPS, and some or partially hidden like on the Kask Infinity or Lazer Z-1 MIPS, potentially making them a little harder to work with while wearing thicker gloves or with cold hands. Our favorite dials have 360-degree accessibility, like on the Bell Stratus MIPS, which are large enough to be adjusted while wearing gloves or with numb fingers.
The ARS fit system on the Lazer Z-1 MIPS has a tensioning knob on the top of the helmet.
The Roc Loc 5 fit system has a small tab system that can adjust the fore/aft position of the headband by 2 cm.
Weight
Road cycling is a gram-conscious sport where both professional and amateur riders go to great lengths to decrease their riding weight. Every extra gram can slow you down on climbs, and a heavy helmet can also cause neck fatigue on a long ride. While helmet weight can certainly impact comfort, all of the helmets we tested are relatively light compared to the overall marketplace, so these comparisons are relative to the models tested in our lineup.
We weigh each product ourselves to get an objective comparison, as the manufacturer claimed weights can often be inaccurate. We're happy to report that every helmet we measured was within 5% or less of the claimed weight, which is essentially equivalent when accounting for potential measurement tolerances and precisions.
Interestingly, some of the more expensive products we tested like the Lazer Z-1 MIPS and the Kask Infinity are heavier than some of their more affordable counterparts. There are several factors for this. Many of the higher-end helmets have more polycarbonate shell material covering the EPS foam liner, which marginally increases weight but also increases durability. Most helmets in our lineup also include an internal MIPS liner for additional crash protection, adding 20-30 g to their non-MIPS equipped counterparts. We feel that the modest increase in weight for a MIPS liner is outweighed by the potential safety benefits. More aerodynamic helmet styles like the Kask Infinity or the Specialized S-Works Evade typically have a longer profile and fewer vents, which increases the helmet material and the overall weight.
The elongated, semi-aerodynamic profile of the Airnet adds to the weight and the bulk of this helmet.
You don't always need to spend extra money to achieve weight savings. The aerodynamic model Bontrager Ballista scores well in the weight metric. The model we tested was without a MIPS liner which likely contributed to the weight savings.
Style
The aesthetic appeal of a road bike helmet is subjective because, as they say, beauty is in the eye of the beholder! However, many of the helmets in our lineup have unique design features that aren't really accounted for in any other rating metrics. This is where we shine the spotlight on features like rubber sunglass holders, retractable vents, or distinctive aesthetics.
The Smith Overtake scores highly in our style ratings, thanks to its modern matte color finish, and the use of Koroyd material that allows for a decreased thickness of the EPS foam liner. Koroyd is a honeycomb-like composite structure that Smith claims will absorb impact more effectively than EPS foam. The result is a range of sleek, low-profile helmets that also accommodate the storage of sunglasses on top of the helmet. The Kask Infinity also stands out in this category with its sweet aerodynamic design, nifty retractable vent system, and nine different color configurations.
We like the matte gray finish on this model, and appreciate how its low profile seems to hug the shape of our head.
We also would like to take a moment to recognize the unique aesthetics of the Catlike Kompact'o Urban! While we recognize that everyone has their own style, many of our testers think this is one of the most attractive models on the market, and appreciate its whimsical character that stands out in a sea of more ordinary designs.
While the tester could use a bit more style, the KOMPACT'O is all style.
Ventilation
A well-ventilated helmet helps keep your head and core temperature down, helping enhance comfort and performance. As aerodynamic designs become a higher priority for helmet manufacturers, balancing aero design with ventilation has increasingly become a challenge. The best-ventilated helmets are not necessarily those with the most vents, but rather the ones that pair properly placed vents with internal channeling for optimum airflow. Aero helmets such as the Kask Infinity, Specialized S-Works Evade, and the POC Octal Aero have fewer vents and tend to be hotter, especially at the low speeds often experienced on a steep climb.
The Specialized Airnet is the best-ventilated road bike helmet we tested. Air movement and heat evaporation are quite noticeable thanks to 21 well-placed vents. On some helmets, the internal MIPS liner can block some of the vents, but that's not an issue with the Airnet. The MIPS liner aligns perfectly with the vents, and there is no airflow restriction. Another standout helmet is the Catlike Kompact'o, which uses just 21 vents to perform as well as the heavily ventilated Lazer Z-1 MIPS with its 31 openings.
Lower scoring products, such as the POC Octal Aero and Specialized S-Works Evade can be stiflingly hot on even moderately warm days. Another surprise was the Smith Overtake which appears to be heavily ventilated, but the hollow Koroyd tubes block each vent. While these tubes do allow for passive heat escape, their orientation lets in very little air. While aero helmets typically sacrifice ventilation for a sleeker profile, the Kask Infinity scores reasonably well with its retractable vent cover that gives the option of switching between more ventilation or more aerodynamics.
One of the coolest things about the Kask Infinity is cruising (read: grinding in pain) up the side of a mountain with the vents open, catching a breeze, then cresting and opening the vent to slice down the side.
Durability
The EPS foam found in most helmet liners is a relatively soft material that is prone to dents and abrasion. The most durable road helmets have a protective polycarbonate shell that extends down around the base of the foam liner, leaving very little of the liner exposed. Helmets with this type of full-wrap shell tend to get banged up less during everyday use. However, many helmet manufacturers choose weight savings over enhanced shell coverage. No matter how well a helmet is constructed, they are typically one-hit-wonders when it comes to a crash impact, so our durability assessment identifies the ability to withstand daily abuse and accidental bumps and scrapes.
The Smith Overtake and Kask Protone find themselves at the top of the pack in our durability ratings, with almost no exposed EPS foam on the exterior of the helmet. The polycarbonate shell extends around the base and covers nearly the entire upper portion of these helmets. The Specialized Airnet also receives high marks, with a wraparound polycarbonate shell that protects the helmet base, but has a bit more EPS foam exposed on the upper portion than the top scorers.
The Smith Overtake MIPS has a full wrap polycarbonate shell and a very comfortable set of X-Static pads.
Conclusion
The primary purpose of a bike helmet is to protect your head in the case of a crash, and all helmets sold in the USA are subject to the same minimum safety standards. While all helmets may offer the same basic level of crash protection, beyond that, they are far from equal. Different helmet designs go above and beyond by adding extra features such as MIPS liners for extra safety, adjustable headbands and chinstraps, comfortable padding, and different levels of ventilation. Our testers racked up hundreds and hundreds of miles in the saddle, through all sorts of conditions, to sort through the differences in each helmet to help you find the best model for your next ride!
The Synthe rides away from the peloton with our Editors' Choice Award.
— Nick Bruckbauer & Ryan Baham