Abstract: An automatic tester for the hardness of materials is disclosed in which the operations are automated and in which the possibility of human error is significantly eliminated. Particularly, a linear digital encoder is employed which is attached to the capstan and elevating table arrangement. Pulses are developed according to the movement of the penetrator in the workpiece and are utilized to standardize and measure the time during which the major and minor loads are applied to the workpiece. Additionally, use of a CPU according to certain preset procedures and methods allows for enhanced reliability of the testing procedures. Conversions from different testing scales as well as corrections of certain factors is easily accomplished. Still further, the tester includes the provision to insure that certain ASTM standards are met by testing the device with standard test blocks and comparing results with those preset in the CPU.