Slic3r
Slic3r is free software that turns 3D models into printer instructions by slicing them into layers, creating toolpaths, and calculating extrusion amounts.
What Slic3r is
Slic3r is free software that turns 3D models into printer instructions by slicing them into layers, creating toolpaths, and calculating extrusion amounts. It generates G-code for FFF/FDM printers and includes a projector and host for DLP printers. Model conversion supports STL, OBJ, AMF, and POV formats, with SVG slice export. A USB/serial host can control multiple printers with separate spool queues, and jobs can be sent to OctoPrint. The command-line tool supports batch G-code generation, slicing, model cutting, transformations, repair, and format conversion. Libslic3r provides reusable C++ components and a granular API for applications using Slic3r algorithms. Listed advanced functions include multiple extruders, variable layer heights, sequential printing, honeycomb infill, mesh cutting, modifiers, and automatic supports. Packages are offered for macOS, Windows, and Linux; Linux users need freeglut. The project began in 2011 within the RepRap community and uses the GNU Affero General Public License version 3.
Good
- Free plan at no cost
- Supports FFF/FDM and DLP workflows
- Controls multiple printers with spool queues
- Includes automatic support generation
- Offers command-line and C++ library tools
Watch out
- Linux users need the freeglut package
- Project targets advanced users
- Uses the GNU Affero General Public License
- Support is directed to community channels
Who it suits
It suits advanced 3D-printing users who need detailed slicing, printer control, command-line workflows, or library integration. Novice users may prefer simpler configuration options.
Verdict
Slic3r provides broad slicing, printer-control, command-line, and library capabilities for experienced users. Its advanced focus and Linux dependency should guide setup expectations.
Plans and prices
From Slic3r's own pricing page, checked 9 Oct 2026.
| Plan | Price | What it gives you |
|---|---|---|
| Slic3r | Free | Free software · macOS, Windows, Linux |
The facts
Each one read from Slic3r's own pages, with the date it was checked.
What it does
- Advanced features
- Features include multiple extruders, variable layer heights, sequential printing, honeycomb infill, mesh cutting, modifiers, and automatic support generation.checked 9 Oct 2026
- Audience
- The project says Slic3r is mostly used by advanced users, while novice users often need only a few configuration options.checked 9 Oct 2026
- Command line
- The command-line tool supports batch G-code generation, SVG slice export, model cutting, transformation, repair, and format conversion.checked 9 Oct 2026
- Downloads
- The download page offers precompiled official and development packages for macOS, Windows, and Linux; Linux users need the freeglut package.checked 9 Oct 2026
- Integration
- Slic3r can send jobs to OctoPrint.checked 9 Oct 2026
- Library
- Libslic3r is a C++ library with reusable components and a granular API for building applications on Slic3r algorithms.checked 9 Oct 2026
- License
- Slic3r is licensed under the GNU Affero General Public License version 3.checked 9 Oct 2026
- Model formats
- It supports conversion between STL, OBJ, AMF, and POV formats and can export SVG slices.checked 9 Oct 2026
- Origin
- The Slic3r project began in 2011 within the RepRap community and describes itself as a non-profit, independent community project.checked 9 Oct 2026
- Printer control
- A built-in USB/serial host controller supports multiple simultaneous printers, each with a spool queue.checked 9 Oct 2026
- Printer types
- It generates G-code for FFF/FDM printers and includes a built-in projector and host for DLP printers.checked 9 Oct 2026
- Purpose
- Slic3r converts 3D models into printer instructions by slicing models into layers, generating toolpaths, and calculating extrusion amounts.checked 9 Oct 2026
- Support
- The project directs users to GitHub discussions and its IRC channel for community participation and support.checked 9 Oct 2026
The company
- Founded
- 2011checked 28 Sep 2026
Where it runs
- Machine compatibility
- The project says it supports known G-code dialects including Marlin, Repetier, Mach3, LinuxCNC, Machinekit, Smoothie, Makerware, and Sailfish.checked 9 Oct 2026
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