In this paper we improve an empirical mass formula constructed by J\"anecke and collaborators. This formula is enlightened by the Garvey-Kelson mass relations. The new version of the J\"anecke formula reproduces 2275 atomic masses with neutron number $N\ensuremath{\ge}10$ and proton number $Z\ensuremath{\ge}6$, at an average accuracy of 128 keV, by employing 576 parameters. The predictive power of our formula is exemplified by comparison with predicted results of other mass models.