Slic3r is free software 3D slicing engine for 3D printers.

It generates G-code from 3D CAD files (STL or OBJ).

Once finished, an appropriate G-code file for the production of the 3D modeled part, or object is sent to the 3D printer for the manufacturing of a physical object.

[2][3] As of 2013, about half of the 3D printers tested by Make Magazine supported Slic3r.

[4] Prusa Research maintains an advanced fork called PrusaSlicer.