Accurate modeling of the complex physical interactions between solid Earth, oceans, and ice masses in response to deglaciation processes is of paramount importance in climate change and geodesy, since ongoing effects of the melting of Late Pleistocene ice sheets still affect present-day observations of sea-level change, uplift rates, and gravity field. In this paper, we present SELEN⁴, an open-source code that can compute a broad range of physical predictions for a given deglaciation model.