Drug-resistant epilepsy poses a significant clinical challenge, where resective surgery and intracranial brain stimulation are key strategies when conventional pharmacological treatments fail. In these cases, the implantation of intracranial electrodes enables precise recording and stimulation of specific brain regions. However, a major limitation lies in accurately visualizing and estimating the spatial extent of the stimulated area. This work presents the development of a digital tool — a visualization and optimization software — based on patient-specific electromagnetic modeling. The software integrates magnetic resonance imaging, brain parcellation, and personalized electric models of the patient’s brain. It enables estimation of the spatial distribution of the electric field generated during stimulation, offering specialists a pre-surgical planning platform with improved precision and versatility. This supports the use of advanced stimulation protocols and enhances interpretation of clinical responses, avoiding suboptimal stimulation due to uncertainty in spatial targeting. While the primary focus is on epilepsy, the software is also applicable to other pathologies requiring intracranial stimulation, such as Parkinson’s disease or chronic pain. This tool contributes to more informed and personalized treatment strategies, with the potential to improve outcomes in patients undergoing invasive neurostimulation procedures.