GLB Viewer

Open GLB files online

This GLB viewer opens .glb files in the browser: drop one on the page and you can rotate it, play its animations and see what is packed inside. The file is read on your own device and never uploaded, which matters when the model is an unreleased product or a client's asset.

GLB is the single-file, binary form of glTF 2.0. It is the format most web 3D viewers, product configurators and AR experiences load, so it is also the file you most often need to check before it goes live.

What is inside a GLB file

A GLB is a small container with three parts: a 12-byte header that starts with the letters "glTF", a JSON chunk that describes the scene, and a binary chunk that holds everything heavy. Geometry, skin weights, animation keyframes and texture images all sit in that binary chunk, which is why one GLB can replace a .gltf, a .bin and a folder of images.

Once loaded, the info panel tells you what the file actually contains:

Vertices and triangles

The real geometry cost. A product model for the web is often fine with tens of thousands of triangles; millions usually means an unoptimized scan or CAD export.

Meshes and materials

Many small meshes or materials mean many draw calls, which slows rendering on phones more than triangle count does.

Textures

The number of images packed in the file. Textures are often the largest part of a GLB.

Animations

The number of clips. Play them and pick one from the clip list.

Bounding box

The model's size. glTF uses meters, so a chair should be around 1, not 100 or 0.01. A wrong scale makes AR placement look absurd.

File size

What visitors download. Compare it against the triangle and texture counts to see where the weight is.

Checking size and compression

GLB files are usually compressed in two ways. Geometry can be compressed with Draco (the KHR_draco_mesh_compression extension) or with meshoptimizer (EXT_meshopt_compression). This viewer opens both, decoding them in your browser; your model is not sent anywhere.

If a GLB is heavy but its triangle count is modest, the textures are the problem. Several 4096 x 4096 PNG maps add up quickly. Resizing them, or using JPEG for maps that do not need transparency, often cuts the file far more than mesh compression does. Command-line tools such as glTF Transform and gltfpack can do this in bulk.

Textures compressed with KTX2 / Basis Universal (KHR_texture_basisu) are not supported by this viewer. If a GLB lists them as required, which is the usual case, it won't open here; if it only uses them, the model opens without those textures.

Checking a model from an AI 3D generator

Image-to-3D tools such as Tripo, Meshy and Hunyuan3D deliver GLB files: a single mesh with its colors baked into a texture. Open one here and turn it around before you use it. The generator had to guess the back of the object, and that is where problems hide.

The info panel tells you what you got. Generated meshes are often dense, with tens or hundreds of thousands of triangles, and usually come out about one unit across. Check the triangle count before putting the file on a web page, and the size before printing it.

To print it, convert it with GLB to STL.

Where GLB files are used

Product pages: many e-commerce platforms, Shopify among them, accept GLB for 3D product models, and the widely used model-viewer web component loads GLB.

Augmented reality on Android: Google's Scene Viewer displays glTF and GLB models in AR. iPhone and iPad use USDZ instead, so stores that support both usually keep a GLB and a USDZ of each product.

Games and real-time apps: Godot, Babylon.js, three.js and many other engines import glTF and GLB directly. Blender exports GLB with the "glTF Binary" option.

To make the iPhone version of a product model, use GLB to USDZ.

When you need the separate .gltf files instead

Because everything in a GLB is binary, you cannot open it in a text editor to look at the materials or fix a texture. To inspect or edit the original JSON, you need the source .gltf export. Downloading as glTF from the viewer gives a readable .gltf with the buffers and textures embedded as data URIs, but it is a re-export: Draco compression is removed, materials are converted to PBR and unknown extensions are dropped.

You can also save the model as OBJ, STL, PLY or USDZ. STL is for 3D printing and keeps only the shape; OBJ output contains geometry without materials or textures.

For working with multi-file glTF exports, see the glTF Viewer.