Convert glTF to AMF
Free glTF to AMF converter that runs in your browser. See real dimensions before you download.
How to convert glTF to AMF
- Drop your glTF file (with its textures, if separate) onto the converter — it opens in your browser, nothing is uploaded.
- Check the preview and the dimensions in mm; fix units or the up axis in “Units & orientation” if the size or orientation looks wrong.
- Choose AMF as the output and click Convert. Several files download as one ZIP.
What carries over from glTF to AMF
| glTF | AMF | Result | |
|---|---|---|---|
| Colour / materials | Yes | Yes | Kept |
| Textures | Yes | No | Dropped |
| Units stored in file | Yes | Yes | Written as mm |
| Separate parts | Yes | Yes | Kept |
| Usual up axis | Y | Z | Rotated (switchable) |
About glTF files
glTF was developed by the Khronos Group, the body behind OpenGL and Vulkan, and version 2.0 was released in 2017 and later adopted as ISO/IEC 12113. The design goal was a lean transmission format that engines can load without heavy processing. In its text form, a .gltf file is JSON that lists scenes, nodes, meshes, materials, animations and accessors, and it points to external .bin buffers and image files, though buffers can also be embedded as base64 data. The same content packed into one file is called GLB. Because the JSON is readable, glTF is popular for tooling, pipelines and debugging, and for projects that want to diff or hand-edit assets. It uses metres, a right-handed coordinate system and +Y up, and its physically based materials are supported by most web and game engines.
About AMF files
AMF was standardised as ASTM F2915 and later ISO/ASTM 52915, with the aim of fixing the shortcomings of STL for additive manufacturing. A file is XML, optionally compressed as a ZIP, and describes one or more objects made of a vertex list and volumes of triangles. Unlike STL, it declares units, such as millimetre, inch or micrometre, and can attach colours and materials to volumes or even to individual triangles, with gradients between them. The specification also allows curved triangles, constellations that arrange several objects, and custom metadata. In practice it was overtaken by 3MF, which came from industry backers and gained support in Windows and the main slicers. AMF files still appear from some multi-material printers and research tools, and from older exporters in Cura, Slic3r and Meshmixer.
3D printing notes
glTF is a display format, so a slicer will not open it. Convert it to STL or 3MF first. As with GLB, the main traps are metres versus millimetres and the Y-up axis. A character exported from a game pipeline can also contain separate shells for eyes, clothing and hair that overlap; slicers see overlapping volumes and may print them unevenly. MeshShift reads glTF in the browser, shows dimensions, applies the ×1000 metre-to-millimetre scale by default, and rotates the model upright. The print check rebuilds a single closed solid when you need one. When writing glTF, MeshShift embeds the buffers, so the output is a single self-contained file.
Frequently asked questions
Is this glTF to AMF converter free and private?
Yes. The conversion runs in your browser with JavaScript and WebAssembly, so your glTF file is never uploaded to a server. There is no sign-up, no watermark and no daily limit; very large files are limited only by your device's memory.
Should I use glTF or GLB?
Choose GLB when you want to share, upload or ship one file with textures inside. Choose glTF when you need to read or edit the JSON, keep textures separate, or let a version control system show changes. Both are the same standard and convert losslessly.
Is AMF better than STL?
On paper, yes: it has units, colour, materials and several objects. In practice STL is accepted everywhere and AMF is not, and 3MF now fills the same role with much wider support. Use AMF only when a specific tool or workflow requires it.