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OBJ to 3MF converter

Drop your .obj file — we convert it to .3mf right in your browser. Files never leave your computer.

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Drop your OBJ file here
Accepts .obj · converts to .3mf

OBJ vs 3MF— what's the difference?

OBJ.obj

Human-readable Wavefront mesh format — ubiquitous in 3D graphics, game art, and asset pipelines. Pairs with a .mtl material file.

Strengths
  • Supported by virtually every 3D tool (Blender, Maya, 3ds Max, Unity, Unreal…)
  • Plain-text, easy to diff and hand-edit
  • Keeps UV coordinates and vertex normals, unlike STL
  • Material references via companion .mtl file
Limitations
  • Text format — larger on disk than binary meshes
  • No scene hierarchy, no animation, no skeletons
  • Materials live in a separate file; easy to lose
Typical use: 3D art pipelines, DCC handoff, asset archives
3MF.3mf

Modern successor to STL for 3D printing — carries units, colours, materials, and multiple bodies in a zipped XML package.

Strengths
  • Real-world units baked in (no more "is this mm or inches?")
  • Multi-material, multi-colour, and per-body metadata
  • Compact zipped payload — smaller than equivalent STL
Limitations
  • Not every slicer reads 3MF yet (most do now — Bambu, Prusa, Cura)
  • Less tooling for mesh editing compared to STL
Typical use: Modern 3D printing workflows, multi-material prints

How to convert OBJ to 3MF

  1. 1
    Drop a .obj file onto the page. Companion .mtl is optional — geometry alone is enough for printing.
  2. 2
    Preview the mesh in 3D and verify the triangle count before converting.
  3. 3
    Click Download .3MF. Load directly in Bambu Studio, PrusaSlicer, Cura, or OrcaSlicer.

FAQ

Why convert OBJ to 3MF for printing?

OBJ is fine for DCC work but slicers prefer 3MF because it carries units, a clean scene graph, and multi-body data. Converting OBJ to 3MF before slicing eliminates the "is this mm or inches?" ambiguity.

Are my textures or materials kept?

The geometry is preserved exactly. Materials inside .mtl are stripped — 3MF for printing normally carries colour at the body level, which most slicers set in their own UI after import.

Does OBJ size matter?

Text-based OBJs can be large. The 3MF we write zips the XML payload, so expect the output to be significantly smaller than the source .obj.

What coordinate system does the 3MF use?

The converter assumes OBJ coordinates are millimetres (the 3D-printing default). If your source is in another unit, scale the print in the slicer after loading.

Is anything uploaded?

No. The OBJ is parsed in your browser and re-packaged as 3MF locally. Your file never leaves your device.

Related converters

OBJ → STLOBJ → GLBSTL → 3MFSTEP → 3MF3MF → STL