Purpose: To develop a mathematical model for calculating twenty-foot equivalent in container trains on the platform given model, to formulate a calculation method in twenty-foot equivalent (TFE) in container trains, to designate a target function in finding optimal filling capacity of fitting platform. Methods: Mathematical calculations were applied using Pascal software environment in terms of automating calculation of fitting platform capacity. Research results: During the calculations, mathematical model design was carried out as well as the study of parameters such as a container mass, size and model was done. Using the analysis of container train load, a target function for the search of fitting platform optimal filling capacity was identified. Practical significance: Review of calculation process for twenty-foot equivalent was carried out by station employees. It is established that as a new element in paperwork chain there should be considered automatic calculation of TFE in container trains, namely, TFE automatic reporting based on the obtained values for TFE in terms of filling in a general form act and a cumulative statement. The description of TFE calculation stages for a one container of 22G1 size on platform given type is demonstrated. Based on the study results, software product in Pascal environment for the calculation of a one container capacity into TFE is proposed.