What exactly does the OFF output contain?

A header, vertex positions in world space, and a face list of triangles. Nothing else — OFF is a geometry-only format.

Why does the model look untextured afterwards?

Because OFF has no material or texture fields at all. The conversion is intentionally shape-only.

How do I know the geometry came through intact?

GLBKit re-parses the generated file and compares its declared vertex and face counts against what was written before you download it.

GLB to OFF Converter

Name: GLB to OFF Converter
Author: GLBKit

Convert a GLB to a plain OFF vertex and triangle face list for geometry libraries. Shape only, no materials. Runs in your browser.

Drag & drop your GLB file here

or click to browse

Supported Formats

.glb.gltf.obj.fbx.stl.ply.3mf.off.zip

Format Information

Source Format

GLB.glb

GLB (glTF Binary)

GLB is the binary packaging of glTF 2.0. Meshes, materials, image textures, animation and the node hierarchy are all written into one file, so an asset can be dropped into an engine or a web page without shipping a folder of sidecar files.

What it carries: Vertex positions, normals, UVs and vertex colours, full PBR materials (base colour, metallic/roughness, normal, occlusion, emissive), embedded image textures, node hierarchy, skinning, morph targets, keyframe animation, cameras and lights.

Open a GLB file in the viewer

Target Format

OFF.off

OFF (Object File Format)

OFF is a minimal, human-readable geometry format from the Geomview project: a header line, a count line, then a list of vertex positions and a list of polygon vertex lists. There is deliberately nothing else in the specification.

What it carries: Vertex positions and face index lists, written out as triangles. No normals, no colours, no UVs, no materials, no textures and no animation.

Open a OFF file in the viewer

About this conversion

OFF is the smallest thing this converter can write: vertices and triangles, nothing else. It is the right output when the next tool is a geometry kernel that wants a plain, unambiguous surface — not when appearance matters.

Why convert GLB to OFF

Feed a computational-geometry library that reads Geomview-style OFF.
Get a trivially parseable triangle file for a custom loader or a test fixture.
Produce a geometry-only copy for shape comparison or a diff-friendly text file.

What happens during the conversion

Geometry

Every mesh is triangulated, transformed into world space and written as a single vertex list plus a face list. The output is re-parsed and its vertex and face counts are checked against the source before the file is handed back.

Materials and textures

Nothing is written. OFF has no material, texture, colour, UV or normal field, so the result is pure surface geometry and a viewer will shade it with a default material.

Animation

A GLB can hold keyframe animation, skinning and morph targets, and OFF stores positions and faces — that is the whole specification. Every rig, clip and morph target is discarded, and what is left is a static surface frozen in the pose the scene was in.

Common use cases

Preparing input for a geometry-processing or mesh-analysis library.
Creating a shape-only test asset for a custom renderer.
Producing a minimal file when you only care about the surface.

Limitations of this conversion

Normals, UVs, vertex colours, materials and animation are all discarded — OFF stores positions and faces only.
Everything is triangulated and merged, so object boundaries are lost.
Because there is no material, the model will look flat in any viewer. This is a geometry export, not a look-preserving one.

How to convert GLB to OFF

Three steps in the browser. Nothing is uploaded to a server, so an unwieldy file is limited only by your own device's memory.

STEP 1

Drop in your .glb

The one self-contained .glb is read directly and its triangles written to a plain OFF list.

STEP 2

Convert to OFF

The scene is triangulated, moved into world space and written as a validated vertex/face file.