4. DraftSight: DraftSight is a powerful 2D and 3D CAD software that also offers a portable viewer version for accessing and viewin... DraftSight DWG FastView-CAD Viewer&Editor
Engineers who need advanced measurement tools for free. dwg viewer portable top
A powerful free viewer that supports over 50 file formats, including DWG and IFC. Large infrastructure and BIM projects. Pros: Incredible detail and measurement tools. Cons: High system resource usage even when portable. 4. IrfanView (with CAD Plugin) dwg viewer portable top