STL vs 3MF
3MF was created to replace STL for 3D printing. Where STL is just a list of triangles with no units, 3MF is a zipped package that records units, colours, multiple objects and even print settings. Modern slicers such as Bambu Studio, PrusaSlicer, OrcaSlicer and Cura read both. STL is still the most widely shared format, but 3MF is the better choice when you control both ends.
Side by side
| STL | 3MF | |
|---|---|---|
| Full name | stereolithography mesh | 3D Manufacturing Format |
| Created by | 3D Systems | 3MF Consortium |
| Introduced | 1987 | 2015 |
| Encoding | binary or ASCII | ZIP archive of XML |
| File size | compact in binary; repeats every shared vertex | small, because it's zipped |
| Materials | No | Yes |
| Textures | No | No |
| Animation | No | No |
| Colour | no colour or materials | colours and print settings |
| Units | unitless (slicers assume millimetres) | millimetres, stored in the file |
| Best for | 3D printing slicers | modern slicers like Bambu Studio, PrusaSlicer and OrcaSlicer |
Choose STL when
- •You're sharing on a model site where STL is expected.
- •The recipient uses older software that may not read 3MF.
- •It's a single-colour part and you only need the shape.
Choose 3MF when
- •You print in multiple colours or materials and want them kept.
- •You want units recorded so the model never imports at the wrong scale.
- •You want to save plates and print settings together with the model.
Which apps open them
Of the 15 3D apps in our software guides, 9 open STL without conversion and 6 open 3MF. Only STL opens directly in Blender, 3ds Max, Sketchfab.
Questions
- Is STL better than 3MF?
- Neither is better everywhere. You're sharing on a model site where STL is expected: choose STL. You print in multiple colours or materials and want them kept: choose 3MF.
- Can I convert STL to 3MF?
- We convert 3MF to STL, but not the other way yet. Export 3MF from the app that made the STL file instead.
- Which file is smaller, STL or 3MF?
- STL: compact in binary; repeats every shared vertex. 3MF: small, because it's zipped. Actual size depends mostly on polygon count and texture resolution.
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 Spotted something out of date?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.