glTF to GLB

glTF to GLB: pack a model into one file

This page converts glTF to GLB in your browser. Drop the .gltf file together with its .bin and texture images, check the preview, and download a single .glb with everything inside. Your files are not uploaded.

glTF and GLB are the same format in two packagings. A .gltf is a JSON text file that describes the scene and points to other files: one or more .bin buffers with the geometry and animation data, and the texture images. A .glb wraps the JSON, the buffers and the images into one binary file. Both are glTF 2.0; neither is better at storing a model. The difference is practical: one file is easier to share, upload and keep intact.

How to convert glTF to GLB

1. Select or drop the .gltf, its .bin file(s) and its texture images, all at once.

2. Check the preview: textures should be visible, and the info panel should count the animations you expect.

3. Click Convert. The .glb downloads straight away.

4. Check the size of the new GLB, shown afterwards. “Download again” saves another copy.

Need a format older software can open? See GLB to OBJ.

Why pack it into one file

A multi-file glTF works well while you are editing it. It breaks easily once it leaves your folder:

Uploading

Many websites, marketplaces, AR services and content tools accept a single file. They take a GLB, not a .gltf plus a folder.

Sharing

Email or chat a .gltf without its .bin and the recipient gets nothing. A GLB can't lose its parts.

Web pages

One request instead of several, and no relative paths to keep right on the server.

Embedded glTF

A .gltf with base64-embedded data is a single file already, but base64 is about a third larger than the raw bytes. Converting to GLB stores the same data in binary.

What is kept, and what to watch

The converter reads the glTF and writes it out again as GLB. That is a re-export, not a byte-for-byte repackaging, so a few things are worth knowing:

Meshes, scene structure

Kept. The model is Y-up in both forms, so no rotation is applied and there is no up-axis checkbox for this conversion.

PBR materials and textures

Kept, with the textures embedded. Textures are re-encoded during export, and any larger than 4096 px are scaled down, so their byte size can differ from the originals.

Animations

Kept.

Draco and Meshopt compression

The input is decoded so it can be displayed, and the GLB is written without that compression. A compressed glTF can therefore produce a noticeably larger GLB. Recompress it afterwards with a command-line glTF tool if size matters.

Less common extensions

Extensions that three.js doesn't read or write may not survive. Check the preview against the original if your model relies on unusual material effects.

Units

Unchanged. Both are in meters.

When the glTF won't load

Almost every failed glTF to GLB conversion is a loading problem rather than a conversion problem:

Missing .bin or textures

The .gltf only references them. A missing .bin stops the model from opening, and the message names the file; a missing texture just leaves that surface without it. Select the .gltf, every .bin and every image at the same time, or drop them all together.

glTF 1.0

Not supported. Files from before 2017 may use version 1.0. Check the asset version in the JSON; re-export from the source program as glTF 2.0.

KTX2 / Basis textures

Not supported. If the file lists them as required, it won't open; if it only uses them, the model loads without those textures. Export with PNG or JPEG textures instead.

Grey model

One or more image files weren't selected, or their names differ from the uri values in the .gltf.