Convert OFF to glTF
Free OFF to glTF converter that runs in your browser. See real dimensions before you download.
How to convert OFF to glTF
- Drop your OFF file onto the converter — it opens in your browser, nothing is uploaded.
- Check the preview and the dimensions in mm; fix units or the up axis in “Units & orientation” if the size or orientation looks wrong.
- Choose glTF as the output and click Convert. Several files download as one ZIP.
What carries over from OFF to glTF
| OFF | glTF | Result | |
|---|---|---|---|
| Colour / materials | No | Yes | — |
| Textures | No | Yes | — |
| Units stored in file | No | Yes | Written as mm → metres |
| Separate parts | No | Yes | — |
| Usual up axis | Z | Y | Rotated (switchable) |
About OFF files
OFF, the Object File Format, was defined for Geomview, an interactive geometry viewer developed at the Geometry Center at the University of Minnesota in the 1990s. A file is plain text. The first line holds the keyword OFF, the second gives the counts of vertices, faces and edges, then each vertex appears as three coordinates and each face as a vertex count followed by index numbers. Variants add colour (COFF), normals (NOFF) or texture coordinates (STOFF) through prefixes, and colour is optional at the end of each line. The simplicity made it a favourite in computational geometry, and benchmark sets such as ModelNet used it for machine-learning research on shape classification. CGAL and libigl read and write it directly. It has no units, materials or scene structure, so it is rarely a printing format, but converting it is common.
About glTF files
glTF was developed by the Khronos Group, the body behind OpenGL and Vulkan, and version 2.0 was released in 2017 and later adopted as ISO/IEC 12113. The design goal was a lean transmission format that engines can load without heavy processing. In its text form, a .gltf file is JSON that lists scenes, nodes, meshes, materials, animations and accessors, and it points to external .bin buffers and image files, though buffers can also be embedded as base64 data. The same content packed into one file is called GLB. Because the JSON is readable, glTF is popular for tooling, pipelines and debugging, and for projects that want to diff or hand-edit assets. It uses metres, a right-handed coordinate system and +Y up, and its physically based materials are supported by most web and game engines.
3D printing notes
Few slicers open OFF directly, so the usual job is converting a research or dataset mesh into STL or 3MF. Dataset meshes such as those in ModelNet are often unit-less, normalised to a small box and not designed for printing, so they can be scaled to a size of one unit and have thin shells or holes. Set the printed size deliberately, then run a repair. MeshShift reads and writes OFF in the browser, shows real dimensions, lets you rescale, and converts to STL, 3MF, OBJ, GLB or PLY. Its print check finds holes and flipped normals and can rebuild a closed solid at the same size before you slice.
Frequently asked questions
Is this OFF to glTF converter free and private?
Yes. The conversion runs in your browser with JavaScript and WebAssembly, so your OFF file is never uploaded to a server. There is no sign-up, no watermark and no daily limit; very large files are limited only by your device's memory.
What is an OFF file used for?
OFF is a simple mesh format used mainly in geometry processing and machine-learning research. Datasets like ModelNet ship as OFF because the format is easy to parse. It is a plain text list of vertices and faces.
Should I use glTF or GLB?
Choose GLB when you want to share, upload or ship one file with textures inside. Choose glTF when you need to read or edit the JSON, keep textures separate, or let a version control system show changes. Both are the same standard and convert losslessly.