The Climbing Shoe Rubber Comparison
Everything you need to know about the best climbing shoe rubbers.
Have you ever spared a minute to think about your climbing shoe rubber? You probably should, understanding a bit about your rubber might just help you climb harder.
Unless you climb barefoot like Charles Albert, the rubber you are using is going to have a big impact on your climbing. Without the right rubber, achievements like Nalle Hukkataival sending V17, Adam Ondra leading 9c or Alex Honnold free soloing El Capitan would surely be impossible.
In homage to this unsung hero, here’s a breakdown of the confusing world of rubber and a deep dive into some of the best climbing shoe rubber on the market.
What is Climbing Shoe Rubber?
The Rubber found on climbing shoes today is made from a mixture of synthetic rubbers. Fillers like Clay and Carbon Black are common in all climbing shoes but each brand has its own highly secretive formulas for its trademark rubbers.
When recreational mountaineering was becoming popular with adventurous Victorians in the late 1800s, these daring adventures used boots – including the sole – that were made entirely from leather.
It wasn’t until Charles Goodyear discovered the process of vulcanization (a process that increases the strength and flexibility of latex) in 1844 that the trend of using rubber for shoes really begun.
So when rock climbing started developing in the early 20th century, it was only natural for rock pioneers to use their bulky mountain boots. Climbers quickly realized the need for improved shoes, which lead to groundbreaking models like the PA boots.
The first real shoe that paved the way for the future of climbing shoe rubber was the Boreal Fire. In the 1970’s, Boreal reinvented the climbing shoe by creating the first rubber specifically designed for climbing.
The shoe was so revolutionary that the climbers reported jumping an entire grade after using them.
Soft vs Stiff climbing Shoes
One key element to understand about climbing rubber is how stiff or soft it is. Both soft and stiff rubber have their benefits and downfalls which will untimely have an impact on your climbing.
The pros know this, that’s why Adam Ondra climbed Silence (the world’s first 9c) using both the La Sportiva Miura and Solution.
The rigidity of a shoe can be controlled by the thickness of the midsole and the rubber outsole. Deciding between soft or stiff climbing shoes ultimately comes down to what you are standing on.
Stiff Climbing Shoes
Stiff climbing shoes have thicker midsoles and sole rubber, which create a small sturdy platform for you to stand on.
While a stiff shoe will certainly decrease sensitivity and reduce how well you can “feel” the rock, the unyielding strength of a stiff rubber is ideal for inspiring unwavering confidence on the smallest of holds.
Sure, stiff shoes won’t do you any favours on a dynamic bouldering problem but the thicker rubber will inevitably last longer than a wafer thin sole of sticky rubber.
Best For: Trad and big-wall climbers tend to favour stiffer shoes as the reduces strain on your muscles and ligaments making for a come comfortable experience.
A note for the newbies: If you are brand new to climbing, a stiffer shoe will help you to start developing your muscles, ligaments and technique. The strain climbing put on your toe’s is significant, so make sure to build up experience a bit before moving to the ultra-soft shoes.
Soft Climbing Shoes
Soft climbing shoes are designed so that is as little between you and the rock as possible.
This makes them extremely sensitive and allows the shape of your foot to conform to the shape of the hold you are standing on. Think of these shoes like sticky rubber socks, that are ideal for smearing or hooking.
Unlike a stiff shoe, there is little support in these, so your foot and leg muscles are working a lot hard, so are more suited to bouldering or single-pitch climbing.
Best For: Soft climbing shoes are ideal for climbing large volumes of indoor gyms, or for hooking jugs on a steep overhung routes.
A note for the newbies: Soft shoes are really good for developing footwork and will make you a lot more aware of your positioning and balance.
To summarize: In danger of sounding like a broken record, the stiffness of rubber depending what you are standing on. If you are working on a vertical boulder with microscopic footholds, a stiff shoe is what you need. If you are working on a monstrous overhang, you will want soft shoe that will conform to deliver maximum friction.
Types of Climbing Shoe Rubber
The most debated topic when it comes to climbing shoes is the type of rubber your shoes are packing. The quality of the rubber will directly effect the grip, durability, and edging performance of your shoes.
Shoe manufacturers recognize the importance of high quality rubber, which is why companies like Vibram and Five Ten spend millions of dollars developing their secret rubber formulas.
There’s a pretty extensive selection out there, but there are certainly some front runners in this race. Here is the best climbing rubber that can be found on shoes right now.
Important: The rubbers qualities will vary depending on the model of shoe. The 3mm Xs Grip 2 on the La Sportiva Futura feels very different
Vibram is the king of mountaineering rubber and has been since 1937. The company was born after several friends of the company’s founder, Vitale Bramani, died in a mountaineering expedition in the Italian Alps. He thought that poor quality footwear was partly to blame for his friends deaths, so spend the next two years developing a high-quality rubber that would be reliable, in even the toughest terrain.
It wasn’t until 1988 that the company introduced Vibram Grip, its rubber specially designed for free climbing. Ever since then the line has been improved and expanded to meet modern climbing needs.
Vibram Xs Grip – A performance rubber that’s designed to help you climb at your best on any rock surface. Semi-stiff in nature, Xs Grip can be found on a range of La Sportiva, Scarpa and Tenaya shoes and is favoured by some big names including Chris Sharma and Jimmy Webb.
Vibram Xs Grip 2 – The Grip 2 provides superior grip and durability than its predecessor. Designed specifically for overhang climbing, it’s softer than the Xs Grip and is certainly more versatile with a great balance between edging and smearing capability. It is found on most of La Sportiva’s and Scarpa’s high-performance shoes and ideally suited to aggressive sport climbing and bouldering shoes.
Vibram Xs Edge – Widely known as one of the best edging rubbers in the game, the Xs Edge is ideally suited to big wall climbing and multi-pitch routes. While it’s stiffer than its counterparts, the rubber has found its way into some of the most popular bouldering and all-round climbing shoes including the La Sportiva Miura and the Scarpa Instinct VS.
Virbam XS Flash – The newest rubber to enter the Vibram family is the Xs Flash. Designed specifically for indoor climbing and plastic walls, this non-marking rubber that is extremely soft and provides a great level of friction.
Note: A lot of climbers ask about Vibram XS Grip VS Xs Grip 2 VS Xs Edge. These are all tried and tested rubbers that are made for different purposes. The Xs Edge is certainly a lot harder, so will perform better for multi-pitch climbing than it’s counterparts. Xs Grip and Grip 2 are made for different purposes too. The Xs Grip is more general use and the Xs Grip 2 a softer, sticker compound that is focused on perormnace.
Stealth Rubber (Five Ten)
The late Charles Cole, founder and former president of Five Ten, was the man behind the legendary Stealth rubber, an invention which shook the climbing world.
As well as a cult-like following and a host of celebrity fans, the rubber has been dubbed the highest-friction rubber in the world by some of the biggest outdoor publications including; Rock and Ice, National Geographic Adventure and Climbing magazine.
With a fanbase like that, you know Five Ten are doing something right. Five Ten now manufacture 3 rubbers:
Stealth Mi6 – Stealth Mi6 excels on overhung routes and is known as some of the stickiest rubbers ever. A super high friction rubber that can smear on even the most polished rock. The trade off with this rubber being so soft is that is is not very durable. It’s not uncommon to hear fellow climber at the crag complaining about the very short lifespan of their Mi6 shoes.
Stealth Hf – The Hf rubber is found on Five Ten’s performance shoes, such as the Team and Dragon and has been on the market for over 10 years. This soft rubber comes into its on steep, overhung sport routes and bouldering problems. Similar to the Mi6, this high friction, sensitive rubber will wear fast. Like very quickly.
Stealth C4 – The C4 is the most commonly used rubber in the Stealth arsenal and the one that brought Five Ten legiond of loyal followers This compound delivers a more durable rubber than the other Stealth compounds, and can be compared the Vibram XS Grip 2, but perhaps with a little less durability. It’s found on some of their much loved shoes including the Anasazi and Moccasym.
Trax Rubber (Evolv)
While Trax may not be as popular as Vibram or Stealth, don’t be fooled into thinking this is a second rate rubber. Developed by a team of boffins with Ph.Ds in rubber science (yep, that’s a thing) this rubber as been used by some of the greats – Alex Johnson and Ashima Shiraishi to name a few.
Evolv has developed a range of Trax rubber to adapt to different environments.
Trax-SAS – This semi-stiff compound is the most popular Trax rubber, which can be found on the vast majority of Evolv shoes. Trax-SAS maintains a balance between friction and durability and is designed to perform on rock and plastic holds across a wide range of temperatures, making it a great all-round rubber.
Trax-XE – Found on a few of their newest shoe – including the General and Supra – this super stiff rubber is designed specifically with edging in mind. Found on their ultra performance shoes, this rubber is undoubtedly in its element on granite and slab walls and easily one of the most durable rubbers on the market.
Trax-GT – The newest addition to the Trax family is the GT rubber, cooked up the the Evolv labs with the sole purpose for plastic and gym climbing. This long lasting, non-marking material isn’t found on many of there shoes – yet.
FriXion Rubber (La Sportiva)
Vibram (Xs Edge and Xs Grip 2 in particular) rubber is found on many of La Sportiva’s performance shoes. However, often La Sportiva’s more affordable models feature their FriXion rubber. La Sportiva have been developing their FriXion line to consist of 5 different compounds, of which only two are currently used for climbing shoes, with the rest being used on their running and approach shoes.
FriXion Black – Their stiff FriXion rubber which is used on budget shoes including the Tarantulace and the Oxygym. Described as an ‘ultra sticky performance compound’ that puts performance over durability. From our experience, we find that FriXion black tends to preform better on plastic than rock.
FriXion Eco – The FriXion eco preforms very similar to the black, but uses recycled components and off cuts from production that would usually have to be the discarded. This rubber is found on La Sportiva Eco shoes including the Cobra Eco and Mythos Eco.
FriXion White – A recent addition to the FriXion family is the White. Similar to the Trax-GT, this is created as a non-marking durable rubber designed for indoor climbing. As of yet, no La Sportiva climbing shoes come standard with FriXion White, but we are looking forward to see what creations La Sportiva cook up with this rubber in the future.
Climbing Shoe Rubber Comparison
Every since the first climbing shoes touched rock, climbers have been debating which shoe has the stickiest rubber.
Unfortunately, comparing and coming up with a definitive answer to this question isn’t as easy as it sounds.
The reason for this is because temperature, weight and surface all impact the ability and effectiveness or the rubber. Different rubbers are also designed for different tasks and surface types.
It also depends what you class as the best. While there are certainly some rubbers that are stickier than others, they will almost certainly be less durable than their counterparts.
There was an experiment done in 2007 by Steven Won – a professor at Northwestern University’s Department of Physics and Astronomy – that attempted to determine the stickiest climbing shoe rubber.
The experiment involved comparing 9 of the most popular climbing rubber (at the time). The method involved cutting a 2×2 inch piece of each rubber and placing them on a flat rock. A weight was then put on top of the rubber and the angle of the rock was increase until the rubber slipped off. The angle at which the rubber slipped was then recorded and the experiment was repeated on a flat concrete hold.
Based on this, Steven Won concluded that the following rubbers had the best friction:
1) Evolv Trax XT-5
2) La Sportiva FriXion
3) Vibram XSV
4) Mad Rock FX5
5) Vibram XS
6) Stealth HF
7) Stealth C4
While this experiment was a good start at comparing climbing rubber, the results of this experiment are debated.
For example, the temperature remained constant across all the experiments but as I have already mentioned temperature as a huge effect on how well some rubbers perform. The experiment could have also benefited for using other types of rock and not just a granite slab, as some rubbers would certainly perform better on limestone or sandstone.
Now You Know!
Congratulations, you now know a thing or two about climbing rubber! Make sure to bore all your friends with all this useless knowledge you have learnt.
While your friends might not benefit from this information, your climbing just might. Next time you are being shut down on those fiddly micro footholds, why not slip on a pair of stiff pair of climbing shoes? Or if you current rubber just isn’t making the cut, why not try another one out?
About the Author Katie
Being born and raised in Colorado, Katie knows a thing or two about a good adventure.
If she’s not tied onto a cliff or bombing down a mountain, you will probably find her behind her laptop planning her next adventure.