Durometer (Shore A/D) Hardness Guide
Turn a durometer number into something you can picture. Enter a Shore A or Shore D reading to see what that hardness feels like, everyday materials at the same firmness, and the approximate value on the other scale.
Hardness guide
This material firm but still visibly compresses under a thumb. Everyday examples near this hardness: car tire tread, rubber feet & bumpers, shoe sole.
Reading the Shore scales
Shore hardness tells you how firm a rubber or plastic is by measuring how far a standard indenter sinks into it. The softer the material, the deeper the indenter goes and the lower the number. A pencil eraser sits around 30 Shore A; a car tyre tread and most rubber feet are near 60; a skateboard wheel is up around 90.
Choosing hardness is a trade-off. A softer pad grips and cushions better but compresses, spreads, and can mark a floor. A harder pad holds its shape and carries more, but grips less and transmits more shock. For feet and bumpers, the middle of the Shore A range is usually the sweet spot.
Frequently Asked Questions
What is durometer, or Shore hardness?
Durometer is a measure of how much a material resists a small spring-loaded indenter pressing into it. The most common scales are Shore A for flexible rubbers and Shore D for hard rubbers and rigid plastics. Higher numbers mean harder material.
What's the difference between Shore A and Shore D?
They use differently shaped indenters and different spring forces. Shore A spans soft gels up to hard rubber (0–100A), while Shore D starts where Shore A tops out and runs into rigid plastics. A very hard rubber around 95–100 Shore A is roughly 48–58 Shore D.
How hard are typical rubber feet and bumpers?
Most rubber feet, bumpers, and grip dots land in the 50–70 Shore A range — firm enough to carry a load and stay in shape, soft enough to grip and cushion. Softer than that grips more but marks and compresses; harder grips less but wears slowly.
How accurate is the A-to-D conversion?
It's an approximation. The two scales only overlap at the hard end, and published conversion charts vary, so treat the equivalent as a ballpark. When hardness really matters, measure the actual part on the scale you care about.
Conversions are approximate and based on published overlap charts. Measure the real part when hardness is critical.