Open an OBJ file and get it ready to print
Drop the .obj and it opens in 3D. Each named object in the file becomes its own part, faces with more than three corners are split into triangles, and the model can be repaired and saved as STL or 3MF for the slicer.
No server processing
No account
No daily limits
Saves model files for your slicer, never printer code. Opened and sliced in PrusaSlicer, OrcaSlicer, Bambu Studio and Cura.
What a .obj file is
OBJ is a plain-text 3D format from Wavefront that almost every 3D program reads and writes: a list of points (v lines) and of faces joining them (f lines), with optional texture coordinates, normals and materials in a separate .mtl file. Only the shape matters for printing, so textures and materials are left out here.
Models from Blender, games and scans are made to look right on screen, not to be printed: they are often open at the bottom, made of separate pieces that pass through each other, or far too detailed. Here they are repaired into one closed solid, reduced if needed, and saved as STL or 3MF.
What you can do here
Repair that keeps the shapeHoles are closed along their own edges and flipped triangles are turned, rather than rebuilding the model out of voxels — the surface stays where it was. Checked with PrusaSlicer on real broken models from Thingi10K.
Cuts that fit back togetherCut along any axis or at any angle and add round or square pegs — two or more, so the parts cannot twist — with a gap you choose for your printer. If the cut face is too narrow for the size you set, smaller pegs are used and you are told. Or holes in both parts and separate pins.
Solid geometry, not guessesCombine, subtract and cut run on Manifold, the open-source geometry library OpenSCAD and Blender use for the same job — the result is always a closed, printable solid.
Made for your slicer, not your printerIt saves model files, never printer code: temperatures, speeds and the G-code come from your own slicer and printer profile, and nothing here changes them. Saved files were opened and sliced in PrusaSlicer 2.9, OrcaSlicer 2.4, Bambu Studio 2.8 and Cura 5.13 — 3MF with painted colours, STL, OBJ and STEP (Cura reads no STEP on its own). As with any model, look at the slicer preview before you print.
Nothing to installWorks on Windows, Mac, Linux and a Chromebook, where Meshmixer and 3D Builder do not and where Bambu Studio cannot repair a model. The model never leaves your browser — nothing is uploaded.
Convert OBJ to something else
Questions
- The .mtl file and textures?
- They are not needed for printing a single colour and are not read. The shape comes only from the .obj.
