Convert STP to DWG (STEP to DWG)
To convert STP to DWG (STEP to DWG) you need a 3D CAD program, because a STP file holds solid models and a DWG can hold either those solids or 2D views drawn from them. This viewer cannot do the conversion (it reads DWG and DXF, it never writes DWG), so this page explains the two kinds of result, then the AutoCAD, FreeCAD, Fusion 360, and Onshape routes.
What a DWG of a STEP file can mean
STEP (ISO 10303, extension .stp or .step) is the neutral exchange format for 3D solids: a bracket, a housing, a pump. "Convert it to DWG" means one of two different things, and you should decide which before picking a tool.
3D DWG: the solids are imported into a DWG as AutoCAD 3D solid objects. You can section, rotate, and measure them in AutoCAD or BricsCAD. 2D DWG: front, top, and side views are projected from the model into flat lines, with hidden lines dashed, the way a manufacturing drawing looks. A laser cutter, a draftsperson, or an architect placing equipment on a plan wants the 2D kind. A machinist checking fits wants the 3D kind.
Tools that only handle 2D formats cannot help here: ODA File Converter converts between DWG and DXF versions only, and online "stp to dwg converter" sites usually produce a 3D DWG that then still needs views made. The reverse task is on DWG to STEP.
Which method for which case
| Goal | Tool | Notes |
|---|---|---|
| 3D solids inside a DWG, you have AutoCAD (not LT) | IMPORT the STEP in AutoCAD, save | Fast; AutoCAD LT cannot import STEP |
| 2D views, free | FreeCAD: import STEP, TechDraw views, export DXF or DWG | DWG export needs ODA File Converter installed |
| 2D views, polished drawings | Fusion 360 or Onshape: insert STEP, create drawing, export DWG | Cloud based; Onshape free plan keeps documents public |
| Both 3D and 2D, you have BricsCAD or SolidWorks | Open STEP directly, Save As DWG, or make a drawing | BricsCAD Pro handles STEP natively |
| Quick, non-confidential | Online STEP to DWG converter | Uploads your part geometry |
How to convert STP to DWG with FreeCAD (free)
- Install FreeCAD (Windows, macOS, Linux) and, for DWG output, ODA File Converter. In FreeCAD go to Edit > Preferences > Import-Export > DWG and set the path to the ODA converter.
- File > Open the .stp or .step file. It loads as one or more solid bodies in the Part workbench. Check units: STEP is normally in millimeters.
- For a 3D DWG: select the bodies, File > Export, choose "AutoCAD DWG" or "AutoCAD DXF". FreeCAD writes the solids as 3D faces and meshes, not true solids; if you need real solids in AutoCAD, use AutoCAD's IMPORT instead.
- For 2D views: switch to the TechDraw workbench, insert a default page, select the body and insert a Projection Group. Pick the front view direction, enable the views you need (top, right, isometric), set the scale, and tick hidden lines if required.
- Add dimensions in TechDraw if the drawing should carry them.
- Select the page and use File > Export, or TechDraw's "Export page as DXF"; then convert that DXF to DWG with ODA File Converter (see DXF to DWG), or export DWG directly if the ODA path is configured.
The 2D export contains lines, arcs, and splines on a flat plane, which is exactly what a 2D viewer or a cutting program expects.
AutoCAD, Fusion 360, and Onshape
In full AutoCAD, type IMPORT, choose the STEP file, and the solids appear in the model space of the current drawing; SAVEAS gives you a 3D DWG. To get 2D views from it, create a layout and use VIEWBASE > From Model Space, which places base and projected views on the sheet with hidden lines, then FLATSHOT or export the layout if the recipient needs plain 2D geometry in model space.
Fusion 360: upload the STEP to a project, open it, then File > New Drawing > From Design. Place the views, add dimensions, and use Output > Export Sheet as DWG. Onshape works the same way in the browser: import the STEP into a document, create a Drawing tab from the Part Studio, and right-click the drawing tab to export it as DWG or DXF. Both keep layers for visible lines, hidden lines, and dimensions, which makes the result easy to clean up.
What to check after conversion
- Units and scale. STEP in mm imported into an inch drawing is 25.4 times too small. Measure an overall length.
- 2D or 3D. If the recipient's viewer shows only a bounding box or nothing, you sent 3D solids where flat views were expected.
- Hidden lines. Should be dashed on their own layer; TechDraw and Fusion do this when enabled.
- Splines. Curved edges export as splines; some CNC software needs them converted to polylines or arcs.
- Version. Pick a DWG version the recipient can open; see DWG versions.
For the 2D result, drag the DWG onto dwgviewer.app: the measure tool confirms the scale and the layers panel shows whether hidden lines got their own layer. Nothing is uploaded. If you only need a DXF for cutting, STEP to DXF is the shorter route.
Frequently asked questions
How do I convert a STP file to DWG for free?
Use FreeCAD: open the STEP, make views in the TechDraw workbench, and export the page as DXF, then convert to DWG with the free ODA File Converter, or export DWG directly once the ODA path is set in FreeCAD's preferences.
Can AutoCAD open STEP files?
Full AutoCAD imports STEP with the IMPORT command and creates 3D solids. AutoCAD LT does not support STEP import.
Will a STEP to DWG conversion give me a 2D drawing?
Only if the tool creates projected views (FreeCAD TechDraw, Fusion 360 drawings, Onshape drawings, AutoCAD VIEWBASE). A plain import gives 3D solids inside the DWG.
Can ODA File Converter convert STEP to DWG?
No. It converts between DWG and DXF versions only. STEP needs a 3D CAD program.
Is an online STP to DWG converter safe?
It uploads your part geometry to a third-party server. Fine for a public sample, not for proprietary parts; FreeCAD does it locally.
Can this viewer open the resulting DWG?
It opens 2D DWG drawings in the browser so you can measure and check layers. Its focus is 2D geometry; use a 3D CAD program to inspect solids.