Compact and Lightweight Axial Extensometers are widely used for testing materials such as advanced composites, metals and polymers. These Axial Extensometers can also be used to test round and flat specimens to perform tensile, compression and cyclic tests. These Axial Extensometers include circuitry for auto-calibration against internal shunt reference, thus obviating the need for on-site calibration during installation. Compact and Lightweight Axial Extensometers can operate both in tension and compression modes and are compatible with any strain gage electronics.