Why does my model come out untextured?

Because STL cannot store textures. It holds triangle positions and normals only, so any material in the GLB is intentionally dropped.

Is the output binary or ASCII STL?

Binary STL — the compact form that slicers and mesh tools read fastest.

Does STL support animation or a scene hierarchy?

No. STL is a flat triangle list with no scene graph, so object transforms are baked into the vertex positions and nothing else survives.

GLB to STL Converter

Convert a GLB to binary STL for 3D printing. Geometry and normals are kept; materials and textures are dropped. 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

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

About this conversion

STL is the destination for one thing: getting a shape in front of a 3D printer, a CAM tool or a mesh-processing library that only speaks triangles. Everything that is not a triangle is left behind.

Why convert GLB to STL

Send a model to a slicer. PrusaSlicer, Cura and the rest all take STL as their common denominator.
Feed a mesh-repair or analysis tool that expects a plain triangle soup.
Get a size-stable export for a colleague who needs the shape and nothing else.

What happens during the conversion

Geometry

The whole scene is triangulated and written as a binary STL. Every triangle gets a facet normal. Node transforms are baked in, meshes are merged into one coordinate space, and any n-gon in the source is split into triangles.

Materials and textures

Nothing is written. STL has no material, texture, UV or colour field at all, so a fully textured GLB arrives as an untextured shape that your slicer will colour with its own default.

Animation

A GLB can hold keyframe animation, skinning and morph targets, and an STL is a flat list of triangles with nowhere to put any of it. Only the geometry in whatever pose the scene was authored in is written. If you need the animation to survive, keep the asset in glTF, which uses the identical animation model.

Common use cases

Preparing a model for resin or FDM printing.
Running a mesh analysis or decimation tool that only reads STL.
Sharing a printable shape with someone who has no 3D software.

Limitations of this conversion

All material and texture data is discarded — this is expected for STL, not a bug.
The file is a flat list of triangles: no node hierarchy, no cameras, no lights, no skinning, no animation.
Scale is whatever the GLB used. STL has no unit metadata, so confirm your slicer is interpreting millimetres or centimetres correctly.

How to convert GLB to STL

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

A GLB is self-contained, so the single file is the whole upload.

STEP 2

Convert to STL

The scene is triangulated, normals are computed and a binary STL is written.

STEP 3

Open it in your slicer and check scale

STL carries no unit information — confirm millimetres versus centimetres before you print.