What is in the OFF output?

A header, vertex positions in world space, and a triangle face list. Nothing else — OFF is deliberately minimal.

Can I keep the OBJ material in any form?

Not in OFF. If you need colour, convert to PLY (vertex colours) or to OBJ's modern siblings such as GLB, which keep materials.

Is the output triangulated?

Yes. All faces are written as triangles, and the file is re-parsed to confirm the vertex and face counts match.

OBJ to OFF Converter

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

Drag & drop your OBJ file here

or click to browse

Supported Formats

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

Format Information

Source Format

OBJ.obj

OBJ (Wavefront)

The Wavefront OBJ format is a plain-text mesh description that has been the default interchange format for computer graphics since the 1990s. Geometry lives in the .obj file; colour and texture references live in a companion .mtl file.

What it carries: Vertex positions, normals, texture coordinates and polygon faces, plus what MTL can express: a diffuse colour, opacity, shininess and a single diffuse texture map. There are no PBR metal/roughness values, no normal maps, no vertex colours and no animation.

Open a OBJ 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

A minimal geometry export. The OBJ's positions and faces are triangulated, moved into world space and written as a plain OFF vertex and face list with no appearance data at all.

Why convert OBJ to OFF

Provide input to a computational-geometry library that reads Geomview-style OFF.
Create a tiny, dependency-free surface file for a custom loader or a test fixture.
Produce a text file that is easy to diff when checking shape changes.

What happens during the conversion

Geometry

Every mesh is triangulated, transformed into world space and merged into a single vertex list with a face list. The generated OFF is parsed back and its counts verified before download.

Materials and textures

Nothing. OFF has no material, texture, colour, UV or normal field, so the export is surface geometry only.

Common use cases

Passing a modelled .obj to a computational-geometry library that reads OFF.
Building a shape-only test asset for a renderer.
Reading the result as plain text, so it is obvious which vertex or face a change affected.

Limitations of this conversion

The OFF writer keeps only positions and faces. If your .obj carried normals, UVs, vertex colours, materials or textures, all of it is left behind in the source file — nothing about the input is at fault, but OFF has no field to put any of it in.
OBJ grouping is flattened — everything is merged into one mesh.
The output will render flat in any viewer, because there is no material information.

How to convert OBJ 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

Upload your .obj

Geometry is all the conversion needs.

STEP 2

Convert to OFF

The mesh is triangulated, baked into world space and written as a validated OFF file.