prusa3d/prusaslicer

PrusaSlicer is a desktop program that converts 3D model files into instructions a 3D printer can follow. The conversion process is called slicing: the software divides your 3D design into thin horizontal layers and calculates exactly how the printer's nozzle should move, how fast to travel, and how much plastic to push through at each step. The output is a G-code file, which the printer reads directly. The program accepts common 3D model formats (STL, OBJ, AMF) and supports a wide range of printers, including Prusa's own machines and most other hobby and prosumer printers that use open-source firmware. It also supports resin printers, which cure layers with light rather than depositing plastic through a nozzle. You can load several objects onto the virtual print bed at once and assign different settings to each, so one part can print slowly with fine detail while another prints faster with a coarser result. A 3D preview lets you inspect the sliced layers before starting a potentially hours-long print. Other options include variable layer height within a single print, multiple infill patterns for the inside of solid objects (honeycomb, spirals, Hilbert curves), automatic support structures for overhanging geometry, and a spiral vase mode that produces a smooth outer surface by following a continuous upward path. The program runs on Windows, macOS, and Linux as a standalone application with no additional software to install. It also includes a command-line mode for batch processing or integration with automated workflows, so you can use it without opening the graphical interface. PrusaSlicer started as a fork of Slic3r, an earlier open-source slicer, and is maintained by Prusa Research, the Czech company behind Prusa printers. The source code is licensed under the GNU Affero General Public License version 3, which means it is free to inspect, modify, and redistribute under the same terms.