Fatigue life calculation is crucial for those structures that are applied into a severe dynamic environment, also characterized by high level of randomness. Some commercial software, as Ansys and Comsol, have already built-in tools for random vibration fatigue calculation but Abaqus CAE does not. Hence, this thesis fills this gap, developing a plug-in tool integrated into Abaqus CAE to perform multi-axial fatigue analysis of metal components subjected to random vibration loading. Since this loading is characteristic of high cycle fatigue, first a random stress analysis is perform in Abaqus CAE and then the tool is applied as a post-processor. The literary review suggests some frequency domain methods extremely more efficient compared to time-domain approaches.