DWG to STEP Converter
DWG is AutoCAD's native drawing format, while STEP (ISO 10303) is the universal neutral format for exchanging 3D solid models between CAD systems. Converting DWG to STEP lets you take a 3D AutoCAD model into SolidWorks, CATIA, PTC Creo, Fusion 360 or FreeCAD without losing solid geometry. Note that only 3D DWG solids convert meaningfully to STEP — a purely 2D DWG drawing has no solid geometry to export.
DWG (Drawing) is the proprietary binary format created by Autodesk for AutoCAD. It stores 2D drafting and, in newer files, 3D solids and surfaces.
STEP (.stp / .step) is an ISO-standard neutral format for 3D solid models. It is the most interoperable way to share precise 3D geometry between different CAD packages.
How to Convert DWG to STEP
Open the DWG in a 3D-capable CAD tool
Use AutoCAD, Fusion 360 or free FreeCAD to open your DWG. Confirm it contains 3D solids (not just 2D linework), since STEP represents 3D geometry.
Export / Save As STEP
In AutoCAD use the STEPOUT command; in Fusion 360 or FreeCAD choose File → Export and pick STEP (.stp/.step) as the output format.
Verify the solid model
Re-open the exported STEP file in your target CAD software to confirm the solids, faces and units transferred correctly.
DWG to STEP — FAQ
Can I convert a 2D DWG to STEP?
Not usefully. STEP is a 3D solid-model format, so a flat 2D DWG has no 3D geometry to export. Convert 2D DWG to DXF or PDF instead. Only 3D DWG solids produce a meaningful STEP file.
What software opens STEP files?
Virtually every professional CAD tool: SolidWorks, CATIA, Autodesk Inventor, PTC Creo, Siemens NX, Rhino, Fusion 360 and the free FreeCAD.
Is DWG to STEP conversion free?
Yes — free tools such as FreeCAD and Fusion 360 (free for personal use) can export DWG solids to STEP without any cost.
Will the conversion keep exact dimensions?
Yes. STEP stores precise boundary-representation (B-rep) solids, so dimensions and tolerances are preserved — unlike mesh formats such as STL.