CAPITOLE-RCS is one of the only simulation software in the world entirely dedicated to calculating the RCS (radar cross section) of a military system. It is used by ministries of defense, government technical agency, and defense industry to study the design of weapon systems such as airplanes and ships. Different solvers can be used to simulate from the small complex structure with very high precision to the complete model with efficiency on computation time and computer resources. It allows the radar signature of a system to be estimated during the preliminary design phases in order to guide design choices. It interfaces with the most common CAD formats in order to facilitate exchanges with the mechanical design and structure departments in order to develop high-performance systems. It has been intensively validated with measurement results on reference cases, and by comparison with internal software from major defense manufacturers. The simple and intuitive interface allows engineers to reduce the time spent on model and mesh creation to focus on simulation results.