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Vibration fatigue analysis is a two part process. A structure model mustbe built, be it in a simulated or real environment, which enables the study of stress loadsin material points. On the basis of those stress states, different methods are then used toasses fatigue life. Quite a few frequency domain methods exist, that can operate on obtainedpower spectral densities, to give the fatigue life estimate. The results differ amongmethods and thorough analysis must be made, before such methods can be applied withconfidence. Comparison studies have already been made, but they compare different setsof methods on different data. Based on specifics of structural dynamics responses, a newapproach to comparison has been devised. Different groups of spectra are aimed at evaluatingthe sensitivity of the frequency domain methods on different changes in spectra, suchas changing the distance between modes or raising and lowering the level of backgroundnoise. The accuracy is also tested on some typical accelerated-vibration test spectra,often used in the automotive industry. To come as close as possible to real-world problems,stress data is measured in the form of electro-dynamic shaker vibration. Fatiguelife estimates are compared based on the value of fatigue life given by more conventionalapproach in the time-domain. Conclusions show, that methods by Tovo and Benasciutti,Zhao and Baker and by Dirlik give good results.