<p><b>Abstract</b>—A number of specialized software packages have now been developed for calculating seismic hazard curves. Their algorithmic basis involves the application of numerical methods. A key feature of such calculations is the discretization of the identified earthquake focal zones (EFZ): each zone is divided into finite elements, with each element having seismic activity proportional to its area. In this case, in calculations, the magnitudes of earthquakes also take a discrete set of values. Numerical methods definitely make it possible to solve problems that cannot be described analytically, but they also introduce certain errors. Too coarse a division may not take into account local features of the seismic regime. The accuracy of the final results depends significantly on two key parameters: the selected magnitude discretization step and the principles of dividing EFZs. In this study, we consider a localized seismic source whose event flow strictly follows the Gutenberg–Richter law. To determine the intensity of seismic vibrations, the Shebalin macroseismic field equation is used.</p>