What happens to my glTF PBR materials?

They are reduced to what MTL can express: a diffuse colour, an opacity value and a flattened base-colour texture. Metallic, roughness, normal, occlusion and emissive maps are discarded.

Why do I need to upload a ZIP?

Because a glTF asset is a folder. The .gltf file references an external .bin buffer and separate image files, and the converter needs all of them present at once.

Will an animated glTF keep its animation?

No. OBJ has no animation, skinning or morph-target support, so the model is written as a single static pose.

glTF to OBJ Converter

Convert a glTF asset to Wavefront OBJ with a matching .mtl. PBR maps beyond base colour do not survive. Runs in your browser.

Drag & drop your GLTF file here

or click to browse

Supported Formats

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

Format Information

Source Format

glTF.gltf

glTF (JSON)

glTF 2.0 in its JSON form. The .gltf file is a readable text document that describes the scene and references an external .bin buffer plus separate image files, so a finished asset is a folder rather than a single file.

What it carries: The same scene data as GLB — PBR materials, image textures, node hierarchy, skinning, morph targets, keyframe animation, cameras and lights — but expressed as external file references instead of an embedded payload.

Open a glTF file in the viewer

Target 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

About this conversion

The conversion from the modern glTF scene format to the 1990s one. Geometry, UVs and normals come through; the PBR material graph does not, and what survives is written as a matching .mtl with flattened diffuse textures.

Why convert glTF to OBJ

Open a glTF asset in software that only reads OBJ — older CAD tools, sculpting packages and slicers.
Feed a shader tutorial or a custom WebGL loader that parses OBJ by hand.
Produce a simple text mesh for a repository or a static asset bundle.

What happens during the conversion

Geometry

Vertex positions, UVs and normals are written through and node transforms are baked into the positions, since OBJ has no scene graph. Faces are triangulated, so any polygon with more than three corners becomes triangles.

Materials and textures

Each glTF material becomes an .mtl entry: the base colour goes to Kd, opacity to d, and the base-colour texture is flattened to a PNG referenced by map_Kd. Metallic/roughness, occlusion, normal and emissive maps have no MTL equivalent and are dropped.

Animation

glTF can carry keyframe animation, skinning and morph targets; OBJ cannot represent any of them, so an animated glTF converts to a single static pose.

Common use cases

Legacy tool compatibility where glTF is not on the import list.
Static shape exports for the web with a hand-rolled OBJ loader.
Reviewing a model without shader setup.

Limitations of this conversion

PBR maps beyond base colour — normal, metallic/roughness, occlusion, emissive — are lost.
Vertex colours are not written; per-vertex colour in the glTF is dropped.
Animation, skinning and morph targets cannot be represented in OBJ.
You need the complete asset uploaded; a .gltf without its .bin and images will not load.

How to convert glTF to OBJ

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 the full glTF asset

Zip the .gltf, .bin and image files together — a lone .gltf will not load.

STEP 2

Convert to OBJ

Geometry, UVs and normals are written; materials become .mtl entries with flattened diffuse maps.

STEP 3

Unpack the ZIP before opening the result

A materialised model is .obj + .mtl + PNGs in one folder. Unpack them together or the references break.