How to open a DWG file on Windows
To open a DWG file on Windows 10 or 11, drop it into the browser viewer on this page: it works in Edge, Chrome and Firefox with nothing installed and nothing uploaded. Windows has no built-in DWG reader, but it has more free desktop options than any other platform, including Autodesk's own DWG TrueView and several open source CAD programs. Here is how each one fits.
Open a DWG on Windows in the browser
- Open Edge, Chrome or Firefox and go to the Windows viewer page.
- Drag the file from File Explorer onto the drop zone. The page reads the DWG with JavaScript, converts it to DXF on your PC using LibreDWG in WebAssembly, and renders it with WebGL.
- Zoom with the wheel, pan with the mouse, press fit to view. The status bar lists the entity count so you can tell at a glance whether a complex drawing loaded fully.
- Use the Layers panel, measure distances, print via the browser, or export PDF, SVG and PNG.
The viewer accepts DWG from R14 through 2018+ and any DXF; it does not read DWF or files above 60 MB. On a corporate PC where you cannot install software, this is usually the only route that needs no admin rights.
Free DWG reader for Windows: installed options
| Program | Opens | Notes |
|---|---|---|
| Autodesk DWG TrueView | DWG, DXF | Official free reader; plots with AutoCAD plot styles; DWG Convert tool for version changes. Needs admin rights to install |
| Autodesk Design Review | DWF, DWFX | Free reader for Autodesk's publishing format; not for DWG |
| Bentley View | DWG, DGN, and more | Free viewer from Bentley; light and fast |
| BricsCAD Shape | DWG | Free 3D modeler that also saves DWG |
| Autodesk Viewer (web) | DWG, DXF, DWF, RVT and others | Browser based but uploads the file; needs an Autodesk account |
DWG TrueView is the safest choice when a drawing must plot exactly as the drafter intended, because it uses AutoCAD's own plotting engine. For a quick look, the browser viewer wins on speed. The two are compared in detail at DWG TrueView alternatives.
Open source CAD software for Windows that reads DWG
Open source 2D CAD on Windows is mostly built around DXF, because DWG is undocumented. The practical picture:
- FreeCAD imports and exports DWG once the free ODA File Converter is installed and its path set under Preferences > Import-Export > DWG. It also has a native LibreDWG option on some builds.
- LibreCAD is a clean 2D drafting tool but opens DXF only. Convert the DWG first with the ODA converter, or export from the browser viewer to SVG for reference.
- QCAD community edition reads and writes DXF; DWG support is in the Professional edition.
- LibreOffice and OpenOffice Draw do not open DWG or DXF in a usable way. If you were hoping for open office CAD software, use LibreCAD instead; it is a separate project despite the similar name.
Whichever editor you choose, the format conversion step is the same, and it is explained on DWG to DXF.
Set a default app for .dwg files in Windows
After installing a desktop reader, Windows may still open .dwg files with the wrong program, or offer the Microsoft Store. To fix it: right-click the DWG in File Explorer, choose Open with > Choose another app, pick DWG TrueView or your editor, and tick Always. If you have AutoCAD and TrueView both installed, AutoCAD normally claims the association; change it the same way.
File Explorer thumbnails for DWG come from the Autodesk thumbnail handler that TrueView and AutoCAD install. Without one of them, DWG files show a generic icon, which is normal.
AutoCAD opening in separate windows
A frequent Windows-specific question: AutoCAD opens every drawing as a tab inside one window, and people want two drawings side by side on two monitors. The tabs can be dragged out: grab a file tab and drop it outside the AutoCAD window to float it, then move it to the second screen. To run two independent copies instead, start AutoCAD a second time from the Start menu; each instance has its own window and its own undo history, but blocks cannot be dragged between them, so use CTRL+C and CTRL+V.
If AutoCAD itself is opening in multiple windows unexpectedly, the SDI system variable is set to 1 (single document interface). Set SDI to 0 to return to tabs.
When a DWG will not open on Windows
Start with the extension check: a true DWG begins with the bytes AC10. Then check the version against the reader, and run RECOVER in AutoCAD or TrueView's converter for damaged files. The full checklist is at fix a DWG file that will not open. If the browser viewer opens the file but your installed program does not, the installation is at fault, not the drawing.
Frequently asked questions
How do I open a DWG file on Windows 10 without AutoCAD?
Drop it into the browser viewer on this page, or install Autodesk DWG TrueView, which is free. Both work on Windows 10 and 11.
Is there a free DWG reader for Windows?
Yes: DWG TrueView, Bentley View and BricsCAD Shape are free installs, and this site is a free reader that needs no install at all.
Which open source CAD software for Windows opens DWG?
FreeCAD, with the ODA File Converter configured. LibreCAD and QCAD community edition work with DXF, so convert the DWG first.
Can OpenOffice or LibreOffice open DWG files?
No. Neither suite has a working DWG or DXF import. Use LibreCAD, FreeCAD or the browser viewer.
How do I open two AutoCAD drawings in separate windows?
Drag a file tab out of the AutoCAD window to float it, or launch a second AutoCAD instance from the Start menu.
How do I view DWG files on a PC without admin rights?
Use the browser viewer: it runs in Edge or Chrome with no install and keeps the file on the PC.