Sole Materials Explained

Shoe soles are rarely made from a single material. Most footwear combines two or three materials in layers to balance comfort, grip, durability and weight. This page looks more closely at the materials most commonly found in soles and what each one is generally best suited for.

Rubber

Rubber is one of the most widely used sole materials because it combines flexibility with good grip and reasonable durability. It performs well across a range of temperatures and surfaces, which makes it a common choice for school shoes, work boots, hiking shoes and outdoor casual shoes. Rubber soles can be moulded with deep tread patterns for better traction on loose or uneven ground, or kept shallow and flat for smoother indoor surfaces.

Rubber does wear down with regular use, and the tread pattern gradually flattens. Once the pattern is smooth, grip on wet or loose surfaces is significantly reduced.

Leather

Leather soles are traditionally used on formal and dress shoes. They are valued for their appearance, structure and the way they mould slightly to the wearer's foot over time. Leather soles tend to offer less grip than rubber, particularly on wet tile or wet tar, and they are less suited to wet weather or rough, uneven terrain.

Leather-soled shoes are often built on a construction that allows the sole to be replaced by a cobbler, which can make them a longer-term investment compared to shoes with glued, non-repairable soles.

EVA Foam

Ethylene vinyl acetate, usually shortened to EVA, is a lightweight foam used mainly in midsoles for cushioning. It is common in running shoes, trainers and many casual sneakers. EVA compresses to absorb impact with each step, which reduces strain on the feet and legs during walking or exercise.

Over time and with repeated compression, EVA foam loses some of its springiness. This happens gradually and is not always obvious to the wearer, which is one reason sports shoes are often recommended to be replaced after a certain amount of use even if the outsole still looks intact.

Polyurethane (PU)

Polyurethane is denser and generally more durable than EVA, though usually slightly heavier. It is often used in midsoles where longer-lasting cushioning is needed, and in some work boots and outdoor shoes where resistance to oil, chemicals or abrasion is important. PU can become brittle over very long periods of storage, which is why shoes that have sat unused for years sometimes develop cracks in the midsole even if they were never worn heavily.

Thermoplastic Polyurethane (TPU)

TPU is a harder, more rigid plastic compared to standard rubber or foam. It is often used in specific parts of a sole, such as a heel stabiliser or a structural shank, rather than across the whole outsole. TPU adds durability and support in high-stress areas without adding significant weight.

Choosing Based on Material

When comparing shoes, checking the sole material against the intended use is more useful than relying on appearance alone. A rubber outsole with a deep tread suits outdoor and uneven terrain. A combination of EVA or PU midsole with a rubber outsole suits walking and running. Leather soles suit formal, low-impact, mostly indoor or dry-weather use. Matching the material to how the shoes will actually be worn helps avoid early wear and improves comfort and safety.