Free online GLTF to GLB converter

A viewer, game engine, mobile app, or delivery system may require one .glb file instead of a .gltf file accompanied by buffers and textures. Converting packages those dependencies into a portable asset, reducing the risk of missing files or broken relative paths when sharing or archiving it.

What GLTF files contain

glTF, short for GL Transmission Format, is an open 3D scene and model standard maintained by the Khronos Group. It is used by web viewers and engines, AR and VR applications, game pipelines, Blender, Three.js, Babylon.js, and many 3D-content tools.

A .gltf file is JSON that describes scene nodes, meshes, materials, cameras, lights, skins, and animations. Geometry is commonly stored in a separate .bin buffer, while textures are separate files such as albedo.png, normal.jpg, or texture.webp.

A typical asset folder contains model.gltf, model.bin, and one or more image files. glTF can embed some resources as data URIs, but a .gltf file should not be treated as self-contained unless its referenced resources are embedded.

What GLB changes

GLB is the binary container form of glTF 2.0. A .glb file combines the glTF JSON and binary data into one file; images can also be embedded in its binary data.

GLB is useful where a single upload, attachment, download, or asset-library entry is required. It avoids external-file path failures, but it does not automatically optimize the model, lower polygon counts, resize textures, or improve visual quality.

A GLB is not always smaller than its equivalent glTF folder. It may avoid the size overhead of base64-encoded data URIs, but embedded resources, container alignment, and unchanged textures can make its size similar to or larger than the original package.

Convert a GLTF package to GLB

Use the converter on 101convert.com to create a GLB without installing software. Before uploading, locate every file referenced by the .gltf file, including its .bin buffer and textures; submit the complete package in the form supported by the converter. A conversion performed without required dependencies can produce missing geometry, gray materials, or absent textures.

For a repeatable local conversion, use the Khronos-supported glTF Transform command-line tools. Install a current Node.js release, then install the CLI:

npm install --global @gltf-transform/cli

Run the command from the directory containing model.gltf and its referenced files:

gltf-transform copy model.gltf model.glb

copy repackages the asset as GLB without intentionally simplifying geometry or changing texture resolution. It is appropriate when the requirement is a different container, not asset optimization.

Blender is appropriate when the model must be inspected or edited first. Import it with File → Import → glTF 2.0 (.glTF/.glb), then export through File → Export → glTF 2.0 (.glTF/.glb). Set Format to glTF Binary (.glb), choose the output path, and confirm export options for animations, cameras, lights, and selected objects.

Compatibility and quality checks

A standard container conversion preserves the limits of the source: texture pixels, mesh density, animation data, and PBR material values do not become better merely because the output is GLB.

Target applications must support the glTF version and extensions used by the asset. Draco or Meshopt geometry compression, KTX2/BasisU textures, material variants, GPU instancing, punctual lights, and advanced material extensions may fail or be ignored in software without explicit support.

Use compression or optimization only when the receiving viewer supports the resulting extensions. For example, Meshopt compression and KTX2 textures can reduce download size, but they are compatibility changes rather than a basic GLTF-to-GLB conversion.

Application-specific source features may not export exactly to glTF. Bake procedural materials when necessary, apply required modifiers, and check unsupported rig constraints, video textures, and custom shaders. Open the finished .glb in the destination application and verify textures, scale, transparency, animation playback, cameras, and lighting.