FastComp is a computational tool for the determination of the forces that a composite bolted joint subjected to multiaxial loads supports until failure occurs. The main intention of the present work was the development of a graphical user interface (GUI) for the referred tool that allows its parameterization and the visualization of its output results. Using VTK – The Visualization Toolkit, a computational library for graphical structures, visualization and image processing; C#, an object-oriented programming language; and the design principles of an adequate human-computer interaction, a graphical interface was developed as an efficient and effective means of interaction with FastComp. This interface was then evaluated by some users.