A new computational tool for the fatigue life prediction of composite materials, designated CCfatigue, is presented in this paper. This new software has been developed based on a well-established phenomenological fatigue life prediction methodology. It is capable of performing the calculations necessary to estimate the fatigue life of composite materials under complex cyclic stress states of variable amplitude. Although the software allows the benchmarking of several modules encountered in a complete fatigue life prediction methodology, this paper focuses on the presentation of the software framework and the demonstration of its applicability through the evaluation of the effect of the failure criterion on the fatigue life prediction of the examined materials. Different methods were chosen, programmed and added to the CCfatigue library in order to cover most of the existing concepts regarding the problem of multiaxial fatigue modeling and prediction. The theoretical results produced by the developed software, when compared to available experimental data, proved that there is a prominent effect of the selected fatigue failure module on the estimated lifetime of composite materials loaded under irregular loading patterns. © 2010 Elsevier B.V. All rights reserved.