Format and file size
The inspector names the container it detected (GLB, glTF, OBJ, STL, PLY, FBX, or 3MF) and the size on disk, so you know what you are looking at before it reaches a pipeline.
Free GLB Viewer
Img3D opens GLB and glTF files straight in your browser. Drop a model in, orbit it, and read the numbers that decide whether the asset is ready to hand over: bounding box, estimated vertex count, and file size. The model is never uploaded.
Also opens glTF, OBJ, STL, PLY, FBX, and 3MF files. No account, no queue, no upload.
What the viewer reports
Bounding box
The model bounds on every axis. This is the fastest way to catch an asset that was exported at the wrong scale, or one that carries stray geometry far from the object.
Estimated vertex count
A practical budget number for web scenes, mobile AR, and game engines, where the vertex ceiling is the usual reason a model gets rejected.
Live preview
Orbit, zoom, and check the shape and orientation in the canvas. What you see is what the file contains, loaded from your own disk.
How to open a GLB file in the browser
- Open the Img3D 3D Viewers workspace. It is the second tab in the hero workspace.
- Select Choose model and pick a
.glbor.gltffile. The same picker accepts OBJ, STL, PLY, FBX, and 3MF. - Read the format, file size, bounding box, and estimated vertex count under the canvas, and drag in the preview to inspect the mesh.
- If the model needs a different container, open the 3D Converters workspace and plan the route from your source format to the target one.
GLB and glTF: what the difference actually is
glTF is a JSON scene description: meshes, materials, cameras, animations, and a binary buffer that usually sits in a separate .bin file next to the .gltf. GLB is the same scene packed into one binary file, buffer and images included.
| Container | What travels with it | Where it is the right choice |
|---|---|---|
| GLB | Scene JSON, geometry buffer, and textures in a single file | Engines, AR viewers, marketplaces, and anything that moves between machines |
| glTF | Scene JSON plus sidecar .bin and image files | Editing pipelines where textures and buffers stay in version control next to the scene |
| OBJ | Geometry plus a separate material file | Older DCC tools and simple mesh exchange |
A .gltf that renders on your desk can break the moment someone moves the folder, because the buffer and texture paths travel beside it. That single-file property is why GLB is the format engines and AR viewers ask for.
Checks worth making before you ship a GLB
- Scale and units: compare the bounding box with the size you expect. A model exported at 100 times its real size is the most common import bug in game and AR work.
- Vertex budget: read the estimate against the target platform. Web viewers and mobile AR scenes are comfortable in the tens of thousands, desktop work is not.
- Orientation: confirm which axis is up in the preview before the asset reaches an engine that assumes a different one.
- Textures: upload the texture images to the 3D Utilities workspace to check dimensions, power-of-two status, and a rough RGBA memory estimate.
- Print checks: an STL or 3MF belongs in a slicer. The Img3D STL viewer covers the bounding box and triangle estimate side of that workflow.
Where your file goes
The viewer reads the file in the browser tab, so the model stays on your device. There is no account, no queue, and no size gate tied to a server. Only the AI 3D Generator sends data away, and only the source image, prompt, and seed you supply for a generation run.
Making the GLB, not just checking it?
Img3D generates a GLB from a single image. When the job is a photo of a person, a pet, or a product shot and you want a hosted 3D editor instead of a browser-local check, our sibling site Photo3D runs that path.
Questions about the GLB viewer
Is the Img3D GLB viewer free?
Yes. The viewer runs in the browser, needs no account, and has no upload limit.
Does the viewer upload my model?
No. The file is read by the browser on your device. Only the AI 3D Generator workspace sends a source image to a server.
Which file types can I open?
GLB, glTF, OBJ, STL, PLY, FBX, and 3MF, with a viewer button for each format.
Can Img3D convert my GLB to another format?
The converter workspace maps a route from a GLB source to OBJ, STL, PLY, glTF, or FBX and lists the validation step for that route. It plans the route rather than running a server-side conversion, so you know which path to take before you spend time in a desktop tool.