Just want to view a DWG quickly? I used to recommend DWG Viewer from Brava. OpenText discontinued Brava in 2022. There is no Brava successor. For a free DWG viewer, use Autodesk DWG TrueView / viewers or the in-browser Autodesk Viewer.
If you need editing and measuring, etc. DraftSight is CAD software from Dassault. The free version ended in 2019. It is paid now, with a 30-day trial, not a free CAD app. It requires registration, and it is still rather heavy-duty.
Autodesk has some free DWG viewing software. Last time I tried their TrueView app, I found it to be just too big to be convenient for a quick viewer because it seems to be full AutoCAD with all of the editing tools turned off. It would surely be the most accurate, though, because it’s from the mother ship. Design Review is a free DWF viewer. If TrueView is not installed, this is what you see when you try to view a DWG in Design Review:
Autodesk is also offering a web viewer, which uses their Forge backend.
It takes a moment to display but has sharing and markup features.
