Free online FCSTD to AMF converter

Source format: fcstd

FCStd is the native project file format used by FreeCAD, an open-source parametric 3D CAD application. It stores the full design document, including the model history, sketches, constraints, assemblies or links, materials, and often embedded geometry data. FCStd files are typically used by engineers, makers, and designers who need to preserve an editable CAD project rather than just a finished mesh.

This format is best for ongoing design work because it keeps the model fully parametric. However, it is not a universal exchange format, so many 3D printing and manufacturing tools cannot read it directly.

Target format: amf

AMF stands for Additive Manufacturing File Format. It is an XML-based 3D printing format designed to describe printable objects more richly than older formats such as STL. AMF can store multiple materials, colors, lattice structures, and curved geometry information in a way that is useful for additive manufacturing workflows.

AMF is mainly used in 3D printing and prototyping. Its advantages include better support for modern printer workflows and more expressive object data than plain triangle-only formats. That said, support is not as universal as STL, so compatibility depends on the slicer or printer software you use.

How to perform the conversion

The most reliable way to convert FCStd to AMF is to use FreeCAD to export the model as a printable mesh, then save that mesh in AMF format if your FreeCAD version and export workbench support it. Because FCStd is a parametric CAD project and AMF is a mesh-based manufacturing format, the conversion usually involves tessellation of the solid model.

1. Open the .fcstd file in FreeCAD.
2. Make sure the model is fully built and the body or part you want to export is visible and up to date.
3. Select the final solid or object in the tree view.
4. Use File → Export.
5. Choose AMF as the output format if it is available in your FreeCAD installation.
6. Save the file with an .amf extension.

If AMF export is not available in your FreeCAD build, export first to a common mesh format such as .stl or .obj, then open that mesh in software that can save AMF. In many workflows, the mesh export step is the practical bridge between CAD and additive manufacturing.

For best results, use a high enough mesh resolution so curved surfaces are not visibly faceted, but avoid excessively dense meshes that make slicing slow. In FreeCAD, mesh quality is influenced by the export tessellation settings and the complexity of the model.

Notes on quality, compatibility, or limitations

FCStd is editable CAD data; AMF is not. When you convert, you lose the parametric history, sketches, constraints, and feature tree. The AMF file contains only the printable representation of the model, not the original design logic.

Because AMF support is less common than STL, some slicers and printer tools may not import it correctly or may ignore advanced AMF features such as multiple materials or colors. If your target software has limited AMF support, a simpler mesh format may be more compatible.

Also note that the conversion quality depends on the source model. Very small details, thin walls, or complex curved surfaces may require careful export settings to avoid geometry errors. Before printing, it is a good idea to inspect the exported AMF in a slicer or mesh viewer to confirm that the shape, scale, and orientation are correct.