How to Open STL Files in OrcaSlicer
OrcaSlicer is a free, open-source slicer forked from Bambu Studio that supports printers from many brands.
Short answer · Built in
Yes. OrcaSlicer opens STL files as shipped: File › Import › Import 3MF/STL/STEP/SVG/OBJ/AMF (Ctrl+I).
Import STL into OrcaSlicer, step by step
- 1Check the fileFind out what units the part was designed in. Almost every printable STL is in millimetres, but the file itself doesn't say.
- 2Import into OrcaSlicerFile › Import › Import 3MF/STL/STEP/SVG/OBJ/AMF (Ctrl+I).
- 3Check scale and orientationOrcaSlicer works in millimetres and is Z-up. STL files are unitless (slicers assume millimetres), so the size depends on what the exporter assumed.
- 4Place it and sliceLay the flattest face on the plate, confirm the dimensions in the object panel, and slice. Slicers ignore textures and animation.
What comes through
| Shape | Yes, always. |
| Colours and materials | Ignored: OrcaSlicer only uses the shape. |
| Textures | Not used by a slicer. |
| Animation | OrcaSlicer doesn't play animation. |
Things to watch for
- STL is read in millimetres.
- Run the built-in calibration prints (flow, pressure advance, temperature) once per filament; they matter more than model tweaks.
Questions
- Does OrcaSlicer support STL files?
- Yes. OrcaSlicer opens STL files as shipped: File › Import › Import 3MF/STL/STEP/SVG/OBJ/AMF (Ctrl+I).
- Why is my STL model the wrong size in OrcaSlicer?
- STL files are unitless (slicers assume millimetres), while OrcaSlicer works in millimetres. Scale the model after importing, then apply the scale before you continue.
- What is the best 3D format for OrcaSlicer?
- 3MF and STL are the most reliable choice for OrcaSlicer. STL is one of them, so you're already using a good option.
Menu names follow the OrcaSlicer open-source project's current release. Check the official OrcaSlicer documentation if your version differs.
Written with AI assistance by the Renderlyst team in October 2026. Format support reflects each app's current release as we understand it, and we link the official documentation so you can confirm it for your version. Spotted something out of date? Email alishbakhalid766@gmail.com.