This article examines the phenomenon of modern federalism in its geopolitical dimension, underlining the importance of the task of creating a classification system for modern federal states. The author outlines and justifies 10 political and legal criteria of classification, with 32 differentiating characteristics. Each of 24 currently existing federal states receives a unique set of 10 features, presented in the form of a numerical combination. This approach allows us to determine the frequency of combinations of characteristics as well as to identify groups of similar federal states. Such a classification system is universal and allows us to classify not only currently existing federal states but also previous ones.