Convert STEP to DXF

To convert STEP to DXF you project the 3D part onto a plane, either one face for a cutting profile or a full set of views for a drawing, and export that projection. STEP and STP are the same format. This site does not read STEP; it opens the finished DXF in a browser tab so you can check it before cutting.

Pick the kind of DXF you need

Most STEP to DXF requests come from one of three jobs, and each needs a different export:

Cutting shops usually ask for DXF R12 or R14 with all curves as arcs and polylines. Older versions avoid entities that some machine software cannot read, such as splines. If you are not sure which one you need, ask the shop for a sample file they have cut before and match its layers and version.

STEP to DXF in FreeCAD

1. Open the STEP or STP file in FreeCAD (File > Open). The part appears as a solid with its faces.
2. For a cutting profile: select the flat face, switch to the Draft workbench, and run Modification > Shape 2D view. It creates a projection of that face.
3. For a drawing: open TechDraw, insert a page, and add projection views of the part.
4. Select the 2D object (or the TechDraw page) and use File > Export, type "Autodesk DXF". For a page, use TechDraw > Export page as DXF.
5. In Edit > Preferences > Import-Export > DXF you can choose the legacy exporter for R12 output and set how curves are written.

In commercial CAD programs

Programs that read STEP natively usually make this a two-click job. In SolidWorks, right-click a planar face and choose Export to DXF/DWG, or use the flat pattern for sheet metal. In Fusion, create a sketch on the face, project the edges, then right-click the sketch and Save as DXF. Onshape exports a face or a flat pattern as DXF from its context menu. Each of them lets you choose the DXF version on export.

Whichever program you use, check that holes came out as circles rather than polylines made of tiny segments. Some machines run a polyline hole noticeably slower, and it may cut out of round.

Online converters and their limits

Online STEP to DXF converters project the part along one axis and return a DXF. That works for a plate with all its holes on one side. For anything with steps, pockets, or bends, you will get overlapping outlines of every face stacked on top of each other, which no cutting software can use. They also upload your part file, which is a concern for product designs that are not public yet.

If your recipient wants DWG instead, the same views can be saved as DWG; STEP to DWG covers that variant, and DXF to DWG converts a finished DXF.

Check the DXF before sending it to the cutter

Drop the DXF on dwgviewer.app. Measure the overall width and one hole to confirm the scale; a part exported in inches from a millimeter model is the most common and most expensive mistake. Hide layers one at a time to see whether bend lines or dimensions slipped onto the cutting layer. The entity count in the status bar shows whether arcs survived or turned into thousands of segments.

The file is opened inside your browser and is not uploaded. More on the format itself: what is a DXF file and how to open a DXF file.

Frequently asked questions