AMF → BREP

Convert AMF to BREP

Turn an AMF mesh into a BREP file with real CAD geometry. Flat faces, holes, cylinders and cones are recognised and rebuilt as true surfaces, so you can select, measure and edit them.

  • Real planes, cylinders and cones, not thousands of triangles
  • One valid solid that opens in any CAD program
  • Runs on your computer: nothing is uploaded
No file yet
Drop an AMF file or
Files stay on your computer.
Done

How to convert AMF to BREP

  1. Add your AMF file

    Drop it on the converter above or click browse. It opens in your browser, so nothing is uploaded.

  2. Check the format is BREP

    BREP is already selected. You can switch to any other output from the menu.

  3. Convert and download

    Click Convert. Our engine rebuilds the CAD faces, checks the solid, then your BREP file is ready to download.

STL to STEP, done properly

A STEP file you can actually edit.

Other converters wrap every triangle as its own face. Open that in SolidWorks and you get thousands of fragments. We find the real shapes in your mesh and rebuild them, so holes are holes and walls are single faces.

Convert STL to STEP

Typical converter8,202triangle faces
convert3dmodels485real CAD faces, same part
The same bracket as raw triangles on the left and as clean CAD faces on the right

What is AMF?

AMF is an XML-based 3D printing format (ISO/ASTM 52915) that added units, colours and multiple materials to STL. It has largely been replaced by 3MF.

Full name
Additive Manufacturing File Format
Type
Triangle mesh
Used in
PrusaSlicer, Slic3r, some industrial printers
Strength
Units and materials for printing.
Limits
Superseded by 3MF; limited support.
More about AMF

What is BREP?

BREP is the native exact-geometry format of the OpenCascade kernel, used by FreeCAD, CadQuery and many engineering tools built on it.

Full name
OpenCascade boundary representation
Type
Exact CAD geometry
Used in
FreeCAD, CadQuery, Salome, OpenCascade-based tools
Strength
Lossless for OpenCascade-based software.
Limits
Rarely supported outside the OpenCascade family.
More about BREP

Good to know

AMF files store triangles only, so most converters wrap each triangle as its own face. The BREP opens, but every hole is hundreds of slivers and you cannot fillet, measure or edit anything. We analyse the mesh first and rebuild the real shapes.

Mechanical parts convert best: brackets, enclosures, mounts, gears and anything designed in CAD. Organic shapes such as sculptures and scans have few flat or round areas, so they come out as many small flat faces. They are still a valid solid.

Units are kept as they are in the file. Most AMF files from 3D printing are in millimetres, which is what CAD programs expect.

Complex parts can take up to a minute because the rebuilding runs on your own computer. The progress bar shows each stage.

Related conversions

Questions

Can I edit the BREP file in SolidWorks or Fusion 360?

Yes. The result is a solid with real faces. Holes come out as cylinders you can select and resize, and flat walls are single faces you can sketch on or extrude.

Why does my BREP file from other converters have thousands of faces?

Because they turn every triangle of the mesh into its own face. We detect the planes, cylinders, cones and spheres in your AMF and rebuild those instead.

Will an organic or scanned model convert well?

It will convert into a valid solid, but freeform shapes have few flat or round areas, so the result is made of many small flat faces. CAD-designed parts give the cleanest results.

Are my files uploaded?

No. The conversion runs inside your browser, so your AMF file never leaves your computer.

Is there a file size limit?

There is no upload limit because nothing is uploaded. Very large meshes (over about a million triangles) need a computer with plenty of memory.