3MF to OBJ converter

1. Drop your 3MF above.
2. Untick any objects you don't need, or pick a plate.
3. Click Download OBJ. Each object becomes a named object in the OBJ file.

OBJ is a plain-text 3D format that almost every 3D program reads. It's the usual choice for Blender, rendering, game engines and 3D editing tools that don't read 3MF. For printing, STL or 3MF is simpler.

OBJ files don't store a unit, and Blender treats one unit as one metre. This converter writes millimetres, so:

• In Blender's OBJ import options, set Scale to 0.001 to get the real size in metres, or leave it at 1 and work in millimetre-sized units.
• 3D-printing files are Z-up. If the model arrives lying on its side, set the importer's Up axis to Z.

Going from OBJ to Blender and back to a slicer? Wrong scale (often 100× or 1000×) is the most common problem, and it's nearly always the unit setting on import or export.

• Kept: all geometry, object names, and positions.
• Not included: colours (OBJ stores colour in a separate material file), plates and print settings.

3MF (3D Manufacturing Format) was created in 2015 by a group including Microsoft, Autodesk, HP and Shapeways as a modern replacement for STL. Under the hood a 3MF is a ZIP archive with XML inside. It stores:

• Units: millimetres by default, so models open at the right size.
• Several objects, each with a name and position.
• Colours and materials.
• Compact, connected meshes, so files are usually much smaller than STL.

Bambu Studio, PrusaSlicer and OrcaSlicer also save whole projects as 3MF, adding their own extras: build plates, print settings and painted colours. Those extras aren't part of the 3MF standard, which is why a project from one slicer doesn't always open fully in another.

Printing instead? Convert 3MF to STL or open it in the 3MF viewer.