GLB viewer online
Open GLB files instantly — measure in mm, cut a section, spot overhangs and check if the model is ready to print. Nothing is uploaded.
What is a GLB file?
GLB is the binary container for glTF 2.0, the format the Khronos Group describes as the JPEG of 3D. One .glb file bundles a JSON scene description, binary mesh buffers and embedded images, so nothing can go missing in transit. The format was designed for efficient delivery and loading on the web, and it is now used by Three.js, Babylon.js, model-viewer, Google Search 3D results, Meta platforms, Unity and Unreal importers, and many marketplaces such as Sketchfab. glTF defines a physically based metallic-roughness material model, a node hierarchy, cameras, skins and animations. Coordinates are in metres with +Y up and a right-handed system. It is excellent for display and game assets, but it is a presentation format rather than a manufacturing one, so print workflows usually convert it first.
What a GLB file can store
A GLB stores a scene graph of nodes, triangle meshes with positions, normals, tangents, UV sets and vertex colours, PBR materials with base colour, metallic, roughness, emissive and normal maps, and embedded PNG or JPEG textures. It can also carry skeletons, morph targets, animations, cameras and punctual lights. Extensions add compression (Draco, Meshopt), texture formats such as KTX2, and extra material effects. Units are metres, and the up axis is +Y.
Apps that open GLB
Blender, Three.js, Babylon.js, Unity, Unreal Engine, Godot, Sketchfab, Windows 3D Viewer, Reality Composer, Maya.
Strengths
- Single self-contained file with textures embedded
- Defined units (metres) and axis conventions
- PBR materials render consistently across engines
- Open Khronos standard with wide web support
- Supports animation, skins and compressed meshes
Limits
- Not accepted by most slicers directly
- Meshes are often not watertight or single-shell
- Metre scale means a hand-sized model is tiny without conversion
- Compression extensions need decoder support
GLB and 3D printing
Few slicers open GLB directly, so people convert it to STL or 3MF. The two things to get right are scale and orientation. GLB is metres and Y-up, while slicers expect millimetres and Z-up; a 0.1 m figure becomes a 0.1 mm speck if the numbers are read as millimetres. MeshShift multiplies by 1000 on export to STL or 3MF by default, which you can switch off, and rotates the Y-up axis so the model sits flat on the bed. Game-ready GLB files often have open edges, intersecting parts and thin shells, so run the print check and repair before slicing. Colours can be kept when writing 3MF.
Frequently asked questions
How do I open a GLB file without installing software?
Drop the GLB file on this page. It opens in your browser with studio lighting and real dimensions; nothing is uploaded. You can rotate, zoom, measure between two points, cut through the model and check whether it is watertight for printing.
What is the difference between GLB and glTF?
They describe the same scene. glTF is usually a JSON file with separate .bin and image files, while GLB packs everything into one binary file. GLB is easier to share and upload, glTF is easier to inspect and edit by hand.
Why is my GLB tiny after converting to STL?
GLB is in metres and slicers read STL as millimetres, so a 0.15 m model looks like 0.15 mm unless you scale by 1000. MeshShift applies that ×1000 automatically when converting GLB to STL or 3MF, and you can switch it off.
Does MeshShift convert GLB to a printable file?
Yes. MeshShift reads GLB and writes STL, 3MF, OBJ, PLY, STEP and others in your browser without uploading the file. It shows real dimensions first, fixes the up axis, and offers a print check to find holes before you slice.