In order to perform a dynamic calibration of a uniaxial testing system, it is necessary to measure the forces experienced by the test-piece to known levels of accuracy – this measurement is made by a dynamic calibration device (DCD) in place of the test-piece and the calibration method is described in ISO 4965-1. This part of ISO 4965 defnes the calibration procedure for the DCD’s instrumentation. The method for the analysis of the results is also described, leading to a range of testing frequencies over which the instrumentation is valid for use with DCDs in accordance with ISO 4965-1.