AMF was the ISO/ASTM attempt to fix STL for additive manufacturing: curved triangles, colors, materials and constellations in a compact XML file. Adoption ultimately went to 3MF, but AMF files still appear in research and older 3D-printing toolchains.
AMF was the ISO/ASTM answer to STL’s limitations, and it appears in research toolchains, standards sample data and older additive-manufacturing software. Adoption largely moved to 3MF, so most .amf files you meet today are archival.
Best for: Reading legacy additive-manufacturing data. There is a fuller write-up on the AMF format reference page.
Every format on this site also gets the same viewport tools: orbit, pan and zoom with fit-to-view, isometric and the six standard views, a perspective/orthographic toggle, shaded, shaded-with-edges, wireframe and X-ray display, hide-selected, and a PNG screenshot of the current view. The same controls are on the general 3D and CAD viewer, which accepts every importable format at once.
Worth knowing before you rely on it. A viewer that overstates what it can read wastes more of your time than one that is specific about its limits.
| AMF files | |
|---|---|
| Extensions | .amf |
| Geometry | Curved-triangle mesh |
| Units | Yes |
| Colors & materials | Colors & multi-material |
| Animations | No |
| Typical use | Additive manufacturing (legacy) |
AMF declares its unit and the loader converts the geometry to millimetres, so the dimension, area and volume readouts are genuinely millimetre values — one of the few mesh formats here where that is true.
AMF is read-only here. Converting it into a format your slicer actually accepts is usually the point of opening it. The converter runs on the same local pipeline as this viewer, so a conversion is just as private as a preview: AMF to 3MF is the usual choice.
Few desktop tools do, which is the usual reason people end up here. This page parses AMF — plain or ZIP-compressed — in the browser, with objects and volumes in a tree, colors applied and measurements available.
Per-volume and material colors are applied as flat colors, so a multi-material file separates visually. Textures and print metadata are not rendered.
Yes, unusually for a mesh format. AMF states its unit and the loader normalises the geometry to millimetres, so the readouts are true millimetres rather than raw numbers with a label attached.
Generally yes. 3MF won the succession to STL and is what current slicers prefer, while keeping the units, colors and multi-material data that made AMF attractive.
Geometry: curved-triangle mesh. Units: yes. Colors and materials: colors & multi-material. Animations: no. Of that, the viewer draws geometry and flat base colors; texture maps and animation are never displayed. AMF declares its unit and the loader converts the geometry to millimetres, so the dimension, area and volume readouts are genuinely millimetre values — one of the few mesh formats here where that is true.
Read the AMF format reference for the format itself, open the general 3D and CAD viewer if you have several formats to look at, or start from the 3D and CAD converter.
The mesh simplifier does not read .amf directly. To bring a triangle count down, convert to 3MF first, then simplify that. If the file is headed for a 3D printer, the G-code viewer shows the sliced toolpath layer by layer once your slicer has run.
3MF fixes almost everything wrong with STL — units, colors, watertightness, file size. A practical comparison, plus free tools to convert STL to 3MF.
Which file format should you actually print from? A practical ranking of STL, OBJ, 3MF and AMF for FDM and resin printing, with free conversion tools.