jif3d is a framework for joint inversion of different types of geophysical data in 3D. It currently comprises forward solvers for first arrival traveltimes and scalar and tensor gravity data. An interface for magnetotelluric modelling codes is also included. The framework is flexible in terms of the coupling approach between the different datasets. At the moment cross-gradient coupling and deterministic parameter relationships are implemented. Other coupling approaches can be added relatively easilty.