Caligari trueSpace Object .cob
trueSpace objects, from the amateur-3D boom.
What a .cob file holds
COB is Caligari trueSpace’s object format, from a modeller that put 3D on ordinary PCs in the 1990s and was eventually given away for free by Microsoft. Its .scn scene variant is handled by the same reader. Mostly of archive interest now, but a lot of early amateur 3D work exists nowhere else.
Also seen as .scn.
Commonly seen in: trueSpace, 1990s 3D archives.
| Data | Stored in COB |
|---|---|
| Geometry | Yes |
| Materials and colour | Yes |
| Texture maps | Yes |
| Animation and rigs | No |
| Scene hierarchy | Yes |
| Read here | Yes |
| Written here | No |
Tested against a real file
The last sweep loaded spider_4_3.cob from Assimp test models with its 4 sidecar files through the viewer on this site: 1,368 triangles across 4 meshes and 4 materials, in 2.4 seconds. Every format's result is on the test results page, run 2026-09-08.
Convert COB to another format
Every pairing has a page saying what survives the trip.
Other things to do with a .cob file
Questions about COB
How do I open a .cob 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 COB a good format to archive in?
COB stores geometry, materials and colour, texture maps, scene hierarchy. 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 COB 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.