In view of the different concepts and procedures concerning railway infrastructure capacity and the resulting calculations applied by infrastructure managers,this leaflet provides a unique approach to capacity evaluation in the shape of the compression method,which is recommended for those infrastructure managers that use IT support in their evaluations. Unlike the theoretical concepts developed,the compression method is applied to real timetables with practical measurements intended to establish a common understanding of infrastructure capacity. For the first time,a methodology is presented enabling the calculation of nodes capacity based on the same principles.