Abstract: An application program and method for determining the fatigue life of electronic products exposed to vibration, including application program steps of (i) describing the mechanical configuration of the electronic product; (ii) describing the vibration profiles representing environmental exposure; (iii) calculating natural response modes of the circuit card; (iv) calculating stress functions for each component, each response mode; (v) calculating normalized fatigue damage of each component; (vi) removing computer calculation error by comparing the normalized fatigue damage for all components to the expectations; (vii) expectations numerically defined by performing equivalent analyses on test experience results; (viii) for the case of accelerated life testing, using the expectations to determine the adequacy of the design or for the case of product reliability testing, using the expectations to determine the effectiveness of the environmental screen; (ix) for the case of design development, repeating previous s