Error
The file has structural defects that may break viewing or conversion.
GLB/GLTF Validator
Check GLB / GLTF files for header, chunk and JSON structure and common issues, fully local.
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About This Tool
Upload a GLB or GLTF file and the tool checks the container header, chunk layout and JSON structure against the glTF 2.0 specification. GLTF files may reference external .bin buffers and textures — upload them together. Results are shown immediately; nothing is uploaded to a server.
Tips
- 1All checks run locally in your browser
- 2Supports GLB and GLTF (including external .bin)
- 3Fix suggestions are shown per issue
About Configuration Options
Result Severity Levels
Warning
A potential issue was found; verify before use.
Note
Normal structural information about the file.
GLB/GLTF Checks
Magic number
The header must start with the glTF magic 0x46546C67.
Version
GLB version; the current glTF 2.0 spec version is 2.
Total length
The total length declared in the header must match the actual byte count.
Chunk layout
A JSON chunk is required and must come before the BIN chunk.
JSON structure
Required fields and reference integrity of the glTF document.
Minimum size
A GLB must be at least 20 bytes; smaller files are truncated or empty.
BIN chunk
The binary chunk carries geometry data; its bounds must fit the declared length.
asset.version
The JSON chunk must declare asset.version (glTF 2.0).
Format Information
Input format
- Extension:
- glb
- Full Name:
- GL Transmission Format Binary (glTF 2.0)
- Type:
- 3D Model
- Format:
- GLB
- Tools:
- Three.js、Babylon.js、Blender
- Open With:
- 3D Model Viewer、GLB Viewer
- Description:
- GLB is the Khronos open standard for Web 3D, packaging glTF 3D assets and animations into a single binary. Used in Three.js, Babylon.js, and AR/VR apps.
Notes:
- Some 3D printing slicers cannot directly import GLB files
- Not suitable for CAD parametric editing
Supported Features:
- Single self-contained binary file
- PBR material support (base color, metallic, roughness, normal maps)
- Skeletal animation, skinning, and morph targets
- Draco mesh compression and KTX2 texture compression
- Multi-mesh nodes and scene hierarchy
How to Use
1
Upload a file
Drop a GLB or GLTF file
2
Review results
See magic, version, chunk and JSON details
3
Fix if needed
Re-export a valid file from your DCC tool
Frequently Asked Questions
About this tool
Q
What is the difference between GLB and GLTF?
A
GLB is a single binary container that bundles the JSON, buffers and textures into one file. GLTF is a JSON file that may reference external .bin and texture files. Upload them together for a full check.
Q
Can external GLTF files be checked?
A
Yes. External .bin buffers and textures referenced by GLTF can be uploaded together; the tool checks the integrity of these references.
Q
How strictly is the glTF JSON validated?
A
The JSON is parsed against the glTF 2.0 specification: required fields such as asset.version and meshes, buffer and image references, and bufferView/accessor bounds. GLB files additionally get their magic number, version, total length and chunk layout checked. EXT_ or vendor extensions are not interpreted.
Q
My GLTF fails validation: what is usually wrong?
A
The most common causes are invalid JSON, missing required fields such as asset.version, external .bin or texture files not uploaded together with the .gltf, and buffer references that point outside their data. Re-export the file as glTF 2.0 from your DCC tool. The report names the exact field or chunk that failed.
Q
Will the validator repair issues in my file?
A
No. Validation is read-only: neither the GLB binary chunks nor the glTF JSON document are modified. Issues are fixed by re-exporting the file from your DCC tool.
Q
Will a file that passes validation always load?
A
Structural checks rule out common problems in the header, chunks and required JSON fields. Special extensions or business fields required by particular applications are not covered.
General questions
Q
Is Any3D completely free?
A
Yes, Any3D's core features are free to use forever. We provide format conversion, model optimization, and online preview at no cost, with no registration required.
Q
Are my files uploaded to your servers?
A
No. Files you select are processed only in your browser on this device—they never leave your device and are never sent to our servers. We don't store any user files; after processing, related data in browser memory is released.
Q
Do I need to install software?
A
No installation required. Any3D is entirely browser-based—just open the webpage to use all features. It works on Windows, Mac, Linux, and other major operating systems.
Q
Is there a file size limit?
A
The processing capacity depends on your device performance and the model's vertex count and texture complexity, rather than file size alone. We impose no file size limit, but when a model exceeds what your device can handle, the page may lag or even crash.