OFF to glTF Converter
FileFlip converts OFF to glTF entirely inside your browser, using Assimp compiled to WebAssembly. The file is never uploaded to a server: it is read off your disk, converted on your own machine, and saved back by the browser. That means no file-size limit, no queue and no account.
How do I convert an OFF file to glTF?#
- Drop your OFF file onto the converter at the top of this page, or click it to pick one from your computer. You can add as many as you like.
- Leave the target set to glTF and the conversion starts on its own. FileFlip downloads 11.2 MB of WebAssembly the first time and nothing after that, then runs Assimp on your own machine.
- Save the glTF file. Your browser writes it straight to your downloads folder, because there was never a server holding it.
Does converting OFF to glTF lose quality?#
Not in the sense of pixels or samples. Converting OFF to glTF rebuilds the file in glTF's own model rather than re-encoding it, so everything glTF can represent comes through exactly and anything it cannot has to be dropped. Expect the geometry to be exact, and anything the target has no place for, such as a rig, to be left behind.
Is it safe to convert OFF files online?#
Yes, because nothing is uploaded. FileFlip converts OFF files inside the browser tab you already have open, using WebAssembly builds of the same engines a desktop converter would install. Your file is read from your own disk into the page's memory, and no request carrying it is ever made.
You do not have to take that on trust. Open your browser's network panel, run a conversion, and you will see the engine come down and your file go nowhere. There is no upload, no server-side copy, no retention window, and no account tied to what you converted.
How FileFlip works lists every engine, its version and its download size, and shows how to check for yourself that nothing leaves your machine.
What OFF to glTF actually does to the file#
Converting OFF to glTF runs on Assimp, downloads 11.2 MB of WebAssembly the first time and nothing after that, rebuilds the file in the target's own model.
| Engine | Assimp |
|---|---|
| Conversion path | One step: OFF → glTF |
| Downloaded to your browser | 11.2 MB, once, then cached by your browser |
| Quality | Rebuilt in the target's model |
| You get back | One file, or a ZIP when the source carries separate materials or buffers |
| Where it runs | In a background worker, so the page stays responsive |
What survives the conversion
| What is in the file | This conversion | Why |
|---|---|---|
| Materials | Sometimes | Survives for some files and not others. |
| Textures | Sometimes | Survives for some files and not others. |
| Skeleton and animation | Sometimes | Survives for some files and not others. |
Worth knowing before you start:
- the result is a single file when the model has no external materials or buffers, and a ZIP when it does
What is an OFF file?#
An OFF file is plain text written for the Geomview viewer built at the University of Minnesota's Geometry Center, starting with the word OFF and a line giving the vertex and face counts before listing each vertex's coordinates and each face's vertex indices in order.
Use OFF when a mesh needs to move between computational geometry tools or research code that already expects the format.
Convert OFF to OBJ or STL when the mesh needs to open in mainstream 3D software, since OFF support outside academic tools is limited.
What is a glTF file?#
A glTF file is a JSON scene description, developed by the Khronos Group and first released in 2015, that lists a model's meshes, PBR materials, animations and scene hierarchy while its binary geometry and textures sit alongside it in separate buffer and image files.
Use glTF's JSON form when a pipeline needs to inspect or hand-edit the scene structure directly, since it's plain, indexed JSON.
Convert glTF to GLB when the model needs to travel or load as a single file instead of a folder of JSON, buffers and textures.
OFF to glTF questions people ask#
What is an OFF file?
An OFF file is a minimal 3D mesh format: a vertex count, a face count, a list of vertex coordinates and a list of faces given as vertex indices, with nothing else. It comes from Geomview, the visualisation tool built at the University of Minnesota's Geometry Center, and shows up throughout computational geometry research and teaching material.
What software opens OFF files?
MeshLab and Geomview both open OFF files directly, and most computational geometry libraries such as CGAL can read and write it. Outside of research and mesh-processing tools, general-purpose 3D software rarely supports it natively.
Does an OFF file support color?
Yes, an OFF file can carry an optional RGBA colour value on each vertex or each face, appended right after its coordinates or indices. It's the one piece of surface information the format supports beyond raw geometry.
What's the difference between glTF and GLB?
glTF is a JSON text file that references its geometry buffers and textures as separate files, while GLB packs that same JSON, the buffers and the textures into a single binary file. Both describe the identical data model; GLB just bundles everything one file needs to travel as one upload.