This article discusses the development of a cross-platform program "Colour Vision Graphical User Interface", which provides assistance to people with colour blindness. The article characterizes the problem of colour blindness and indicates its relevance, describes methods for solving the problem of colour blindness, considers the stages of creating a program at a theoretical level, describes the main functions and properties that the program should have, performed a comparative analysis of the program with existing analogues, demonstrated the results, tested the program. After creating a cross-platform program, it was tested. This experiment involved people suffering from colour blindness. Based on testing, it was concluded that the program "Colour Vision Graphical User Interface" is really able to help people with colour vision in determining the desired colour. The cross-platform program will be able to find application in the service sector, in educational institutions, as well as in the field of leisure and everyday life. The program will solve the problem of colour blindness so that people with a similar disease can see the world in bright colours and live without restrictions. It also shows ordinary people the world of colour blind people. The program is implemented using C#, C++ and SQL programming languages.