Running shoe midsole materials: EVA, TPU and PEBA foams compared

EVA: the commercial standard

EVA (ethylene-vinyl acetate) is the most widely used midsole foam. It is light, easy to mould into sculpted shapes and cost-effective, which makes it the default for value and core price points. Standard compression-moulded EVA gradually loses rebound with use; higher grades and blends improve softness and durability.

TPU: durable and bouncy, but heavier

TPU (thermoplastic polyurethane) foams, often made from expanded beads, keep their rebound for a long time and resist temperature changes well. The trade-off is weight: a full TPU midsole is noticeably heavier than EVA, so it is often used as an insert or in lifestyle-running styles.

PEBA: light and highly responsive

PEBA (polyether block amide) foams are very light and return a lot of energy. They are used in premium racing and performance shoes. Raw material and processing costs are high, and the foam is softer and less durable than EVA, so it suits premium price points.

Supercritical foaming

Supercritical foaming uses gas such as nitrogen or CO₂ under pressure to expand the material instead of chemical blowing agents. It can be applied to EVA, TPU or PEBA and produces a lighter, more resilient foam. It is a process, not a material — ask which base polymer is being foamed.

Comparison

Material	Weight	Rebound	Durability	Cost level	Typical use
Standard EVA	Light	Moderate	Moderate	Low	Value and core styles
Premium / blended EVA	Light	Good	Good	Medium	Daily trainers
TPU bead foam	Heavier	High	Very good	Medium–high	Cushioned and lifestyle runners
PEBA foam	Very light	Very high	Lower	High	Premium performance

Plates, rockers and air units

• Plates (nylon, TPU or carbon fibre) add stiffness and guide the roll of a tall foam stack.
• Rocker geometry — a curved sole profile — helps a thick shoe roll forward smoothly.
• Visible air units are a strong visual feature and change the cushioning feel in the heel or along the full length.

What to specify in your brief

• The target retail price, because it narrows the foam choice immediately.
• The intended use: daily running, walking, sport-lifestyle or performance.
• The feel you want: soft, balanced or firm and stable.
• Whether the style uses existing sole tooling or needs a new mould.

Material directions on a sample are confirmed during quotation and sample development; ask for the midsole specification in writing before approving bulk production.