Sep 6, 2026Materials & Performance
How to Choose Silicone Hardness for a Functional Part
Silicone hardness is often the first material question in a custom silicone project, but it should not be selected in isolation. The right hardness depends on what the part must...
Silicone hardness is often the first material question in a custom silicone project, but it should not be selected in isolation. The right hardness depends on what the part must do.
What does Shore A hardness tell you?
A lower Shore A value generally means softer feel, higher flexibility and easier compression. A higher value generally means more shape retention, greater resistance to deformation and firmer tactile response.
But hardness alone does not define how a part behaves. Wall thickness, geometry and compression all matter.
For sealing
A sealing feature needs enough softness to conform to the mating surface, but enough structural stability to maintain compression. Too soft can cause excessive deformation; too hard can cause poor conformity.
For keypads
Tactile response depends on silicone hardness, key web geometry, wall thickness, compression distance and housing interaction. Changing hardness alone may not solve a keypad that feels too soft or mushy.
For grips and sleeves
Soft silicone can improve comfort and friction, but very soft materials may stretch during assembly or deform around thin features.
For wearables and skin-contact parts
Comfort matters, but the material also needs to hold shape and survive cleaning.
Use prototypes when feel matters
If tactile feel is important, physical samples are often more useful than choosing hardness only from a datasheet.
Review hardness together with geometry
A thick low-hardness section may feel firmer than a thin higher-hardness membrane. That is why hardness should be reviewed together with wall thickness, compression, support structure and intended load.
Not sure which hardness fits your part? Send the application and target feel for review.
