This thesis will present and explain technologies whose combination allows the use of 3D graphics on the web, and thus study their potential in computer game development. The paper will analyze WebGL, an API for rendering highperformance 2D and 3D graphics within the web browser, and the libraries that evolved from it. 3D modeling techniques and related software will also be studied. The primary research methods will involve examining existing examples of games of this genre as well as techniques for making games in a similar context. The practical part of this paper includes design, creation of necessary elements (2D and 3D) and finally development of a computer RPG game. First, based on research, the concept and key mechanics as well as the story of the game will be specified in more detail. In the production phase, visual identity elements will be created, primarily the logo and user interface. The project will be built following a modular structure, starting with the definition of the basic segments that enable the application itself to function, to the implementation of the main character movement and battle mechanics. The environment will be generated in accordance with the theme of the game. The previously defined user interface will be incorporated into the application to unify the gaming experience. Industry standard methods and tools will be used through the development of the project. Thus, the goal is to organize the code according to best practices, with version control performed regularly. Graphic elements, especially the 3D models will be optimized in the process to enable better performance overall. The aim of this paper is to examine the limits and potential of the aforementioned tools. The limits of how much a single person can independently do within the sphere of such a project will be tested. It is designed as an overview of personal skills and an indicator of progress in the profession. Accordingly, the following hypothesis will be tested: "JavaScript library Three.js and associated tools (HTML, CSS, Parcel, Cinema4D and Figma) allow an individual to design and create a functional computer game."