Abstract Magnetic refrigeration promises to be a breakthrough technology in the field of refrigeration at room temperature. Several magnetic refrigerator prototypes have been developed by research groups, with different embodiments and process thermodynamics. This short paper follows an idealized line connecting, from a conceptual rather than historical point of view, the different geometries, and proposes a classification based essentially on the type of magnetic source, the type of magnetocaloric material, and the relative motion of the active elements of the device. The proposed taxonomy is then applied to some prototype presented in literature, showing its potential to give a comprehensive description of magnetic refrigeration devices by means of a twelve digit string.