Why is my converted STL untextured and white?

Because STL stores only triangle positions and normals — there is no material, colour, UV or texture data in the file to recover. The GLB is given a default material.

Does STL contain units?

No. STL files have no unit metadata, so the converter cannot tell millimetres from centimetres. Check the scale in your target application.

Which STL variants are supported?

Both binary STL and ASCII STL are read automatically.

STL to GLB Converter

Convert an STL to a self-contained GLB with computed normals and a default material, so you can view or publish a print file. Runs in your browser.

Drag & drop your STL file here

or click to browse

Supported Formats

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

Format Information

Source Format

STL.stl

STL (Stereolithography)

STL is an additive-manufacturing format from the 1990s: a flat list of triangles and nothing else. It has no concept of a scene, a material or a texture, which is why it is the lingua franca of 3D printing and also its most lossy interchange format.

What it carries: Triangle positions and, optionally, one facet normal per triangle. No UVs, no vertex colours, no materials, no node hierarchy, no animation.

Open a STL file in the viewer

Target 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

About this conversion

The rescue conversion for a shape that arrived as a bare triangle soup. The STL geometry is read, normals are computed and a default material is applied, producing a self-contained GLB that any modern viewer or engine can open.

Why convert STL to GLB

Open a print or scan file in a proper 3D viewer instead of a slicer.
Load the shape into a web scene, a game engine or an AR experience.
Get a modern, self-contained file you can hand to someone without STL tooling.

What happens during the conversion

Geometry

Every triangle is preserved exactly as stored. The STL's facet normals are carried across as vertex normals, the whole model is placed in a single node, and there is no scene graph to flatten because STL never had one.

Materials and textures

STL has no material concept, so the GLB is given a single default material. There is no colour, no texture and no UV set to recover — the model will render in a uniform shade until you assign materials in a DCC tool.

Common use cases

Inspecting a 3D-printed or scanned model before slicing.
Putting an STL into a web, game or AR scene.
Converting a legacy print file into a modern interchange format.

Limitations of this conversion

The result is untextured and uncoloured. Any appearance must be added after conversion in a 3D application.
STL is usually a single merged mesh, so the node hierarchy and object separation cannot be recovered.
STL has no unit metadata. If the model came from a slicer, confirm the unit interpretation before you scale it.

How to convert STL to GLB

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 .stl

Both binary and ASCII STL are read.

STEP 2

Convert to GLB

The triangles are written into a GLB with computed normals and a default material.

STEP 3

Open it in the GLB viewer

Check the shape and scale, then assign materials in a 3D tool if you need appearance.