Convert glTF to OFF
Free glTF to OFF converter that runs in your browser. See real dimensions before you download.
How to convert glTF to OFF
- Drop your glTF file (with its textures, if separate) 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 OFF as the output and click Convert. Several files download as one ZIP.
What carries over from glTF to OFF
| glTF | OFF | Result | |
|---|---|---|---|
| Colour / materials | Yes | No | Dropped |
| Textures | Yes | No | Dropped |
| Units stored in file | Yes | No | Numbers in mm |
| Separate parts | Yes | No | Merged into one mesh |
| Usual up axis | Y | Z | Rotated (switchable) |
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.
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.
3D printing notes
glTF is a display format, so a slicer will not open it. Convert it to STL or 3MF first. As with GLB, the main traps are metres versus millimetres and the Y-up axis. A character exported from a game pipeline can also contain separate shells for eyes, clothing and hair that overlap; slicers see overlapping volumes and may print them unevenly. MeshShift reads glTF in the browser, shows dimensions, applies the ×1000 metre-to-millimetre scale by default, and rotates the model upright. The print check rebuilds a single closed solid when you need one. When writing glTF, MeshShift embeds the buffers, so the output is a single self-contained file.
Frequently asked questions
Is this glTF to OFF converter free and private?
Yes. The conversion runs in your browser with JavaScript and WebAssembly, so your glTF 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.
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.
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.