EX Durometer / Hardness Tester

EX-A Type Shore A Normal Rubber
EX-D Type Shore D Hard Rubber & Plastics
EX-C Type Asker C Soft Rubber

The Asker Super EX Durometer is a precision instruments for measuring the hardness of various types of rubbers and plastics. Durable metal cases are rugged enough for a production environment. Super EX handheld durometers are easy to use. The easy operation allows for rapid testing with repeatable results. Super EX models are available in Durometer Types: Shore A Hardness, Shore D Hardness and Asker C Hardness.  Select a model number based on the desired testing material.


As the durometer is pressed against the sample, the material resistance force and indenter spring load balance. The depth of the indenter is measured, which provides a measure of the material’s hardness. Values are based upon a 100 point scale (accuracy ±1 point). However, as time elapses the indicator will “creep” back so that a reading taken a few seconds after the indenter makes contact with the sample will be less than the peak reading. Asker durometers offer a peak indicator as an option to more closely monitor the difference between peak and “creep”.

What’s Included with the Durometer?

Asker EX durometers are sold as kits. All new durometer purchases include: durometer, hard plastic carrying case and 3-Point Calibration certficate traceable to NIST.

*Add ‘P’ to the model number to specify optional peak indicator, for example EXP-A.

EX Durometer Selection

ScaleAsker CShore AShore D
IndentorHemisphericalFlat pointCone point
MaterialSoft rubberNormal rubberHard rubber & plastic
StandardJIS K-7312 ASTM D-2240 ASTM D-2240
Measuring Force1 kgf1 kgf5 kgf

Durometer Standards

TypeStandardsMeasuring Force
Shore AASTM D-22401 kgf
Shore DASTM D-22405 kgf
Shore EASTM D-22401kgf
Asker CJIS K-73121 kgf