Formulation of the problem: with the rapid development of information technology, numerous analogues of multidisciplinary programs are increasingly appearing on the software market. Despite the similarity of functions and identical sets of tools, these programs have different graphical user interfaces - program shells that provide the user with the opportunity to interact with the program using logic. In most cases, the overall assessment of users regarding the quality of programs depends on the effectiveness of interfaces. Having a scientific and methodological tool for assessing the effectiveness of interfaces, we can analyze them for the presence of various defects. Currently, there is no comprehensive tool for assessing the effectiveness of interfaces in the scientific literature. The purpose of the work is to develop evaluation tools that allow assessing the effectiveness of software product interfaces in numerical form. Methods: to achieve the stated goal, a comparative analysis of existing quantitative methods, metrics and laws from the scientific literature and international standards for software design and their software interfaces was carried out. Novelty: in comparison with existing methods, the developed approach is presented in the form of an algorithm capable of calculating indicators in the direction of the effectiveness of the compositional equilibrium of graphical user interfaces, which has not previously been evaluated by other researchers. Result: an algorithm has been developed for assessing the effectiveness of the compositional balance of graphical user interfaces, which allows for the evaluation and comparison of software products in this area.