Object File Format .off
Bare geometry: one header, two lists. The academic standard.
What an .off file holds
OFF is about as simple as a mesh format gets: the word OFF, three counts, a list of vertices, and a list of faces indexing them. It comes out of Princeton’s Shape Benchmark and the geometry-processing world, which is where you still meet it: segmentation datasets, computational geometry papers and course assignments almost always ship OFF.
Commonly seen in: Princeton Shape Benchmark, MeshLab, CGAL, Geomview, academic datasets.
| Data | Stored in OFF |
|---|---|
| Geometry | Yes |
| Materials and colour | No |
| Texture maps | No |
| Animation and rigs | No |
| Scene hierarchy | No |
| Read here | Yes |
| Written here | Yes |
Tested against a real file
The last sweep loaded Wuson.off from Assimp test models through the viewer on this site: 3,732 triangles across 1 meshes and 1 materials, in 2.0 seconds. Every format's result is on the test results page, run 2026-09-08.
What we put in an .off file we write
Geometry only, which is all OFF holds. A model with more than one material comes out as COFF with a colour on each face.
Convert OFF to another format
Every pairing has a page saying what survives the trip.
Convert something else to OFF
Other things to do with an .off file
Questions about OFF
How do I open an .off file?
Drop it into the viewer on this site and it opens in the browser, with the scene tree, the materials and the mesh statistics. Nothing is uploaded. If you want it in another program instead, convert it to GLB, which almost everything reads.
Is OFF a good format to archive in?
OFF stores geometry. Anything outside that list will not be in the file at all, so archive the original alongside it if the surfacing or the rig matters.
Does converting OFF lose quality?
Geometry is copied vertex for vertex, so the shape does not degrade. What gets lost is whatever the target format has no field for: convert to STL and the materials go, convert to OBJ and the animation goes. The comparison table on each converter page says exactly which.
Formats that hold the same things
Or go back to the full format reference.