DWG to STL Converter
STL is the standard mesh format for 3D printing, describing an object's surface as a web of triangles. Converting a 3D DWG to STL lets you send an AutoCAD model to any slicer (Cura, PrusaSlicer, Bambu Studio, Ultimaker). As with STEP, only 3D DWG solids convert to STL — 2D drawings cannot be printed.
DWG (Drawing) is AutoCAD's native format. For 3D printing it must contain 3D solids or watertight surfaces, not just 2D linework.
STL (Stereolithography) stores a triangulated mesh of an object's outer surface. It carries no units, colours or precise geometry — just the shape needed to print.
How to Convert DWG to STL
Open the 3D DWG
Open your DWG in AutoCAD, Fusion 360 or FreeCAD and make sure it contains a valid 3D solid.
Export to STL
In AutoCAD run the STLOUT command (or 3DPRINT); in Fusion 360/FreeCAD choose File → Export → STL. Set a fine mesh resolution for smooth prints.
Check the mesh in your slicer
Import the STL into Cura or PrusaSlicer and use its 'fix/repair' option to confirm the mesh is watertight before printing.
DWG to STL — FAQ
Why can't I convert my 2D DWG to STL?
STL describes a 3D surface mesh, so it needs a 3D model. A 2D DWG drawing has no volume to print. You would first have to model it in 3D.
What mesh resolution should I use?
For most prints a medium-to-fine tolerance is enough. Too coarse and curves look faceted; too fine and the file becomes huge. Many tools expose a 'deviation/angle' setting to balance this.
Is DWG to STL free?
Yes. FreeCAD and Fusion 360 (free for hobbyists) both export DWG solids to STL at no cost.
STL or STEP for manufacturing?
Use STL only for 3D printing. For CNC machining or further CAD work use STEP, which keeps exact geometry rather than an approximated mesh.