Leather vs Synthetic Climbing Shoes - Which is Best?

Synthetic materials are getting closer and closer to mimicking leather and have even mastered some aspects of leather imitation. Leather continues to hold the reign of superior strength and durability while also being soft and supple.

There are a few good reasons to debate a leather vs synthetic shoe that we’ll get into below. The following information was collected from interviewing 10+ brands, from designers to product managers, about their shoe models.

If you don’t care about pros and cons and just want to know which shoes are vegan, switch to this All The Vegan Shoes post.

Fit and Feel

Most manufacturers cite a full leather or partially leather footbed as essential for them to optimize the fit, feel, and performance of a shoe. This might just be a small bit of leather in the forefoot, or maybe a bit of leather by the heel. These leather pieces can ensure the shoe lasts a long time, molds to the foot, and/or doesn’t blow out.

Leather is currently the only material the brands cite that can mold to the foot – the more unlined the leather the more molding to the foot. This means the shoe can be more comfortable over time as the shoe literally starts shaping to your foot. In theory, this molding will enable more precise movement (I don’t know of any study to say this is true). This is also why many seasoned climbers claim that a shoe on its ~3rd resole will perform the best; by this time the shoe is fitting like a glove and is essentially brand new in terms of expected performance.

Looking to resole your shoes? Check out this re-soling post.

Many brands said that the need for a leather upper has decreased substantially. There are now synthetics that can match the durability and stretch needed for a shoe’s upper that traditional materials like leather once provided. Some of these synthetic materials can be even easier to tension and work with while creating the shoe.

Most brands also felt that a leather footbed provided a softer feel. Butora, for example, used to have all hemp footbeds, but due to customer feedback switched to leather footbeds on all their shoes.

Takeaway

• Leather molds to your foot, creating a glove like feel that is even more amazing when you resole your shoes where you receive back a “new shoe” (outer) that has been custom molded to your foot (inner).

Stretch and Fit

A benefit of a majority synthetic shoe is consistency – you can count of a lack of stretch. On Day 1, 30, 90, 300, you’ll find the same general fit. This means the day you try on the shoe will be very similar to all the days into the future, which is incredibly helpful for reliably finding the right size.

The amount of stretch for leather shoes can be unpredictable and at times frustrating. A broad rule of thumb is that leather shoes stretch 1/4 – 1/2 size. This partly depends on the design intent of the manufacturer and how they’ve created the shoe to stretch and also what part of the cow the leather comes from. Designers can stop a leather shoe from stretching by lining it with a synthetic material. Unlined leather areas will stretch more than lined leather areas of the shoe.

But, complicating the matter is that often the tighter you buy the shoe, the more stretch you’ll end up having as there is more pressure on the shoe. So it can be a delicate balance that is mostly helped by expert sales associates or shoe demo reps who have a lot of practice and feedback fitting shoes. Reading fit feedback from online reviews can be helpful as well.

There are outliers. The La Sportiva Mythos is notorious for easily stretching 1-2 full sizes. The Mythos uses leather from the belly of the cow that is extremely supple.

When I wore my pair of well-used Mythos on an alpine climb on a cold day and put socks on, that pair further stretched with my sock-sized foot. Since then I have no longer enjoyed the fit without socks (it became my Alpine Sock Shoe).

Takeaways

• You can quickly trust how synthetic shoes fit your foot as there will be minimal stretch throughout its lifespan
• Your shoe size for leather shoes will likely be a little different than your size for synthetic shoes (you can’t assume all of a brand’s shoes in x size will fit the same)
• Unlined leather shoes will stretch more than lined leather shoes

Variations in Quality

Not all leather is the same. Not all cows are the same. Not all parts of the cow are the same. Typically, when leather is bought by a company, and arrives in the shop, somebody is looking at and categorizing the leather. Leather from the neck and back stretch less, the belly stretches the most. Premium cuts often originate from the center of the cow. The pattern maker is looking for consistency in the leather that will mean it has a certain stretch characteristic. They may put certain parts of the leather aside for certain shoe models, or certain areas of the shoes.

For a leather upper they’re also looking for a very uniform leather and ensuring no defects, like if a cow had scratched itself against a fence that left a welt.

Synthetic materials on the other hand are significantly more uniform and don’t need to go through the same type of inspection and sorting process, which can reduce cost in terms of the time involved. Although this cost savings may or may not have an overall impact on the final cost of the shoe, depending on the cost of the synthetic material.

Takeaway

• Manufacturers ensure high quality materials by inspection (for leather) or by buying uniform (synthetic) materials

Shoe Smell

Typically synthetic shoes will hold more moisture which can attract bacteria. This is exacerbated with shoes that are lined with synthetic materials or padded with foam.

Some companies skip lining their synthetic shoes because it will help reduce the smell. The lack of footbed will decrease durability and the footbeds ability to mold to the foot, but the shoe will breath better.

Leather tends to breath better which allows the shoes to dry out which reduces the smell.

We wrote an entire post of how to get the smell out of shoes, but the bottom line is: no matter the material type, after you climb, open up your shoes and expose them to as much air as possible, so they can dry quickly. The worst, most inviting to smells option, is to store your shoes in a closed bag after you’re done climbing.

Takeaways

• Leather shoes stink less than synthetic shoes
• All shoes will stink if you don’t air them out after climbing

Crack Climbing Durability

Every person, from each brand that I asked about durability for crack climbing, said that personally, for crack climbing they preferred leather as they felt it tended to be more durable against abrasion.

While testing, SCARPA found the eco-leather to be weaker than normal leather. To counter this on their shoes, they make the eco-leather thicker than their normal leather, at 2.5mm instead of 2mm. They also bonded a stretchable laminate to the top pieces of the leather upper. Since SCARPA took extra steps to create additional structure, their eco-leather models are actually more durable than traditional leather.

When I asked specifically about how the shoe companies balanced and chose leather or synthetic materials, they touted some synthetic materials could be as durable as leather.

Alas, most brands don’t publish exactly which synthetic materials make up each shoe, nor is there a classification for which ones provide the most durability.

When not talking about crack climbing, there was no durability preference for leather vs synthetic – by the brands, or any individual I interviewed. This makes sense as there are few non-crack-climbing times where the shoe upper is touching/scraping the wall to make a difference.

Takeaway

• While crack climbing it’s safer to buy a leather shoe to ensure maximum durability
• Eco-leather is not as durable as regular leather, but the brands can counter that with additional thickness and/or a supportive backing
• If you’re not crack climbing, the durability of materials in the upper should not make a difference

Sourcing & Eco Leather

Leather comes from a variety of countries, like Mexico, USA, Italy, China, etc. Depending on the country the leather comes from, you’ll have different chemicals and different methods of disposal of the chemicals used in the tanning process. Europe has much higher chemical standards than any other area, so their processes are often safer (despite still using heavy metals) for the factory workers and the exposure risk is significantly less for the environment.

Years ago, when we toured the SCARPA facility, we asked why they didn’t have any vegan climbing shoes (they offer many vegan running shoes). They talked about the myth of vegan shoes being more sustainable and shared how small of a footprint their current process was: They were buying leather that was all sourced in the local area, with the higher European chemical and workplace standards.

Both La Sportiva and SCARPA use Idro-Perwanger leather for their eco-leather. This eco-leather means the leather is free from heavy metals in the tanning process (no chrome or mercury). It is made by Perwanger Leather, who is based in northern Italy. Buying materials from Italy also keeps the transportation factor very low for these Italian brands. According to SCARPA’s website, this eco-leather process also uses less water and is produced with renewable energy.

Another notable difference of eco-leather is that it is biodegradable. Leather is not biodegradable due to the tanning process changing the leather to an inorganic material. At this point we are not aware of any biodegradable synthetic materials used in climbing shoes.

There are many companies making synthetic materials. By far the biggest in the industry is Daewoo, based in Korea. Shoe companies based in Asia buying these synthetic materials will have much less transportation of materials versus their European or American counterparts.

One of the reasons we can’t say either the leather making or synthetic material making process is better because there are so many pieces at play here. Some examples of the complication:

• What chemicals are involved in the process (tanning or material creation)
• How much waste is created / is the waste recycleable (at the origin facility and at the shoe facility)
• How much transportation is involved
• Durability of materials / biodegradability

If you’d like to read more about what the brands are doing that are eco-friendly in the shoe making process, check out this Sustainable Eco-Friendly Climbing Shoes post.

Takeaway

• Without a MAJOR deep dive, there is no surface level ability to say leather vs synthetic is better for the environment.
• Eco-leather is more environmentally friendly than regular leather

Why to choose Leather or Synthetic shoes Summary

Material is a great way to help narrow the options but your ideal climbing style and how a shoe fits your foot matters the most when choosing a shoe.

The reasons to bias your search to a material type are…

Choose Synthetic If

• You want to be sure of the sizing – when you try on the shoe out of the box, the fit will be very similar for the lifetime of the shoe, so there is no guesswork involved in wondering how much the shoe will stretch
• You want a vegan shoe

Choose Leather If

• You want the shoe to stretch to mold/conform to your specific foot, creating the most glove-like possible fit
• You have particularly sweaty feet or if you want all the natural help available for mitigating smelly shoes
• You want to guarantee maximum durability when crack climbing (since it’s hard to tell exactly what synthetic material is being used – it’s a safer bet to go with leather as a known high durability option)