Free OFF (.off) to STL (.stl) converter — running entirely in your browser. No upload, no signup, no file limits: your files never leave your device.
STEP · IGES · BREP · STL · OBJ · PLY · GLB · glTF · 3MF · COLLADA · AMF · FBX · 3DS · OFF · LAS · PCD · XYZ · PTS
OFF is a minimal academic mesh format: a vertex list and a face list in plain text, nothing else. Its simplicity makes it a favorite in computational-geometry research, mesh-processing courses and tools like CGAL and MeshLab.
STL is the de-facto standard for 3D printing. It describes a model purely as a mesh of triangles — no color, no units, no assembly structure — which makes it simple, universally supported, and the required input for virtually every slicer, from PrusaSlicer and Cura to resin-printer tools.
| OFF | STL | |
|---|---|---|
| Geometry | Polygon mesh | Triangle mesh |
| Units | No | No — unitless numbers |
| Colors & materials | Optional vertex colors | No |
| Animations | No | No |
| Typical use | Research & geometry processing | 3D printing |
Yes — free with no accounts, no watermarks and no file-size limits. Conversion runs on your own machine, so there are no server costs behind it.
No. The converter runs entirely in your browser using WebAssembly. Your .off file never leaves your device, which makes it safe for confidential designs.
Yes — parts and assembly hierarchy are preserved where STL supports them, and you can optionally merge everything into a single mesh during conversion.
Yes. Every converted model opens in the built-in 3D viewer with an assembly tree, display modes and section views, so you can inspect the result first.
OFF vertex colors are not carried through the converter’s flat per-part color model, and the format supplies no reliable units. The STL result also has no units, colors, material data or part names, so keep the source alongside it.
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