Soft vs Stiff Climbing Shoes: How do They Differ?

Climbing shoes are a crucial piece of equipment to help you stay safe and comfortable on the rock. Climbers typically have a preferred type of shoe that they prefer, whether it is a soft or stiff shoe. One may think that there is not much difference between these two types, but in reality, each has its benefits for certain situations. So, among soft vs stiff climbing shoes, which is better in terms of rubber material?

With soft climbing shoes, you can downsize more than stiff climbing shoes. More downsizing means a more snug fit. The soft climbing shoes are more sensitive, due to which they offer more transfer of power from heel to toe when you are climbing overhangs. Soft climbing shoes also make smearing easier because they compress when weight is applied – this makes them great for bouldering where feet often slide off of tiny holds. The sole thickness of a soft climbing shoe is up to 3.5mm, and the sole thickness of a stiff climbing shoe ranges from 3.5 to 4.5mm.

Just like size, the softness or hardness of a climbing shoe is a relative factor. A climbing shoe can be softer or stiffer with respect to the other brands. Your weight also affects your performance of climbing in soft and stiffer shoes. So, read this guide till the end as I’ll be giving some examples of climbing shoes based on the skill level and the condition of climbing terrain.

Also Read: Lace vs Velcro Climbing Shoes

Which Factors Determine the Stiffness of Rock Climbing Shoes?

The thickness of midsole and rubber quality would be a couple of the features determining how stiff a shoe is. The thicker the midsole, the more will be its torsional rigidity and lesser flexibility. Soft climbing shoes have a thin midsole and are more flexible. Moreover, different types of rubber affect the stiffness of rock climbing shoes. I’ll discuss them in the later section of this article.

Stiffer Climbing Shoes are More Supportive

A thicker midsole can provide more support and a stable foundation as compared to soft rock climbing shoes. They don’t conform to the shape of a foothold while heel hooking or toe hooking. This makes them suitable if you need to stand on small ledges with only one foot.

Here’s what a climbing expert says about the support of stiffer climbing shoes.

Even a super downsized Skwama (soft climbing shoe) will never be able to edge as well as a TC Pro (the most stiffer shoe), you just can’t get the power that the outside of your foot is pushing to the inside edge.

A stiffer midsole is more reactive to the force you apply during toe or heel hooking. In this way, it is good for beginners who are in the development phase of building the strength of their ligaments.

I found this comment by a person on a forum in which he is recommending stiffer climbing shoes for beginners.

stiff climbing shoes is recommended for beginners

The larger the ledge, the more force a climber must apply to pull his weight. The stronger the force, the stiffer shoe you will need to resist it. If the climbing shoe is soft, it will bend with a large force and absorb its impact.

Soft climbing shoes seem to just smear onto the hold when you try to place your big toe on the hold and put a lot of force onto it from your foot. It will result in hindering the reaction of that force and you won’t be able to pull your weight.

Soft Climbing Shoes Provide More Grip

A stiff shoe will have a harder midsole that won’t deform as much when you put the step on hold. A stiff climbing shoe sits on the top of the foothold. This reduces the amount of grip you can get out of them because they are unable to squish which is what allows the rubber to fully contact the rock and give maximum grip.

Being flexible, a soft climbing shoe can aggressively mold itself to the shape of foothold and give you a much better grip than a stiff rock climbing shoe can. However, as previously discussed, this kind of flexibility is not suitable for small ledges as it will reduce the control over your foot placement.

Stiff Climbing Shoes Are Suitable for Heavy Climbers

Climbers or Mountaineers, weighing over 220 pounds, normally opt for stiffer climbing shoes for support because they weigh high enough to press climbing shoes against holds high enough so that they can achieve the desired friction.

Which Type of Rock is Suitable for Soft and Stiff Climbing Shoes?

Based on previously discussed factors like grip, support, and flexibility, soft climbing shoes are suitable for slabs, and steep overhangs. These shoes are usually made of very soft rubber that provides maximum flexibility, sensitivity, and smearing capabilities thus it’s ideal for low-level climbers who need to feel around the footholds before committing their weight onto them.

If the slab has small positive footholds, the stiffer climbing shoes would work well.

Outside on literal dime edges or the tiny nubbins of smith rock, stiff climbing shoes, you’ll likely need a stiff rock climbing shoe for better edging on the tiny holds. For indoor climbing walls, the footholds are typically larger. So, soft climbing shoes can be used, only if you’re not a beginner.

In the image below, you can see the climber is wearing soft climbing shoes in an indoor gym wall, having large footholds.

soft climbing shoes for indoor gym wall

What Are Different Types of Rubber for Climbing Soft and Stiff Climbing Shoes?

There are many different types of rubber used in the making of rock climbing shoes. Each has its own unique properties which help climbers achieve better performance on specific surface conditions.

Before diving in, keep in mind that the feel of rubber depends on the overall design of the shoe, including the rubber sole thickness.

Vibram Rubber

One of the most widely used rubber in making stiff climbing shoes is Vibram. Vibram is a world leader in high-performance sport shoes with excellent durability. Vibram rubber offers a wide range of hardness levels, as shown in the image below.

vibram rubber grades
Source: Vibram

Vibram rubber has different grades. The first one is Vibram XS Grip. It stands out for its great balance amongst all its features of grip edging performance and durability. It’s made using compounds, having a medium density and a good balance between stickiness, support, and edging/smearing abilities on various stony surfaces. This helps you to climb at any rock surface.

It provides very good results in many kinds of situations and works well on small difficult footholds on steep routes friction slabs and overhanging walls.

The second category is Vibram XS Grip 2. It is very close to the same level of grip as Vibram XS Grip1. However, Vibram XS Grip2 rubber has higher durability. It is suited to aggressive sport climbing and bouldering. It is designed to help you stand on the smallest edges and take advantage of any available rest. You can find Grip 2 rubber on Testarossa, Solution, Futura, Python, and Cobra. 

The third category is Vibram XS Edge. Vibram XS Edge sacrifices some stick (grip) for more durability. It is specially made for edging. This rubber is found in one of the stiffest climbing shoes i.e. TC Pros. It will be great on your comfy size trad climbing shoes. If you’re a heavy person, you can buy climbing shoes with Vibram XS Edge rubber.

Stealth Rubber

This type of rubber is very soft and sticky which makes it perfect for smearing and crack climbing (when you need to use the side of your shoe to press against a cliff face). All Stealth rubbers become soft with increasing temperature.

Stealth rubber has the following categories.

The first one is Stealth Mi6. This category is the stickiest rubber on the market. You can find this rubber on Team VXis. It is literally designed to smear on the polished surface like glass. The molded “full sheet”, as the company calls it, is extremely thin allowing for maximum feel and sensitivity. It wears quickly but smears very well. The sticky and thin sheet of rubber makes it excellent for overhung climbing.

The second category is Stealth HF. It is the second stickiest rubber available. It has insanely high friction and sensitivity. You can find this rubber on 5.10 Dragons. By conforming to even the tiniest edges and crystals, Stealth HF has assisted climbers in scaling steep slopes by allowing them to pull with their feet.

The third category is Stealth C4. C4 is an excellent choice with a temperature less than 40F.  When hot, it cannot hold its edge. It is 5.10’s most flexible rubber. You can find this rubber on Five Ten Aleon. It is considered a competitor of Vibram XS Grip 2. This rubber is suitable to try out on real rock to feel its performance. People call it an all-around rubber that starts as stiff material, but with time, it becomes soft. It is great for It is less durable than Vibram XS Grip2. However, the stickiness makes up for the lack of durability.

The fourth category is Stealth Onyx. It is the hardest rubber of all the soles in Stealth’s lineup. Onyx is a great edging rubber. Onyx wears longer than other grades of Stealth rubber. It feels very stiff when you are pulling on small edges or pockets. Onyx is too hard for indoors. It is not as sticky as C4 or Vibram XS Grip 2. But, the thickness can be adjusted to enhance the grip.

Onyx rubber has some disadvantages. It performs worst in cold months. So, I’d recommend the rubber for only warmer months for better performance.

Soft vs Stiff Climbing Shoes: Final Verdict

The choice between stiff vs soft climbing shoes comes down with your personal preference. Stiff shoes are better for “edging” where you are standing on small edges. Softer shoes are better for “smearing” where you use more friction for your foot placements.

If you’re a beginner, I’d recommend you stiff climbing shoes as they will give you more support on those tiny edges. Even if you plan to eventually get softer climbing shoes, one pair of stiffer ones is good to have around for the times when only a very precise shoe will do.