<p>The field of wave energy converters (WECs) remains underexplored compared to other renewable energies, and with limited investment in research, reducing costs is a key priority for both research institutions and emerging industrial companies. One cost-effective approach is the development of in-house numerical solvers to study the interaction of waves with WECs, rather than relying on expensive commercial software. In this study, a numerical solver based on the boundary integral equation method was developed to compute the three-dimensional hydrodynamic coefficients of WECs. The solver was validated through a combination of computational studies, demonstrating its accuracy and reliability. Additionally, a dynamic module was incorporated to predict the behavior of WECs under both regular and irregular wave conditions. As an application example, the solver was used to calculate the absorbed energy of a point absorber in real sea conditions.</p>