How to open a DWG file
To open a DWG file, drop it into the free DWG reader on this page: the drawing renders in your browser tab and nothing is uploaded. You do not need AutoCAD, an account or an install. Below are the exact steps, the alternatives for desktop and phone, and what to do when a file refuses to open.
Open a DWG file online in four steps
The viewer reads DWG files saved by AutoCAD R14 through the current 2018+ format (internal codes AC1014 to AC1032). It converts the DWG to DXF on your device with LibreDWG compiled to WebAssembly, then draws it with a WebGL renderer.
- Open dwgviewer.app in Chrome, Edge, Firefox or Safari.
- Drag the .dwg file onto the drop zone, or click it and pick the file from disk. The first DWG in a session also fetches a 9 MB WebAssembly module once; later files skip that step.
- Wait for the conversion. A typical 1 to 20 MB drawing appears in 1 to 10 seconds on a laptop. The status bar shows the entity count when it is done.
- Pan with the mouse, zoom with the wheel, press fit to view to see the whole sheet. Use the Layers panel to hide what you do not need, and Measure to check a distance between two points.
From here you can print through the browser dialog or export the drawing as PDF, SVG or PNG. If what you really need is a PDF, the DWG to PDF page runs the same engine with export in focus.
What software opens DWG files
A DWG reader is any program that can parse Autodesk's binary drawing format. Several are free. The table lists the ones people actually use and where they run.
| Tool | Platform | Opens DWG | Notes |
|---|---|---|---|
| DWG Viewer (this site) | Any browser | Yes, R14 to 2018+ | Nothing uploaded, no sign-up; view, measure, export PDF/SVG/PNG |
| Autodesk DWG TrueView | Windows | Yes | Official free reader; also converts between DWG versions. Large install |
| Autodesk Viewer (online) | Browser | Yes | Requires an Autodesk account and uploads the file to Autodesk servers |
| Bentley View | Windows | Yes | Free reader for DGN and DWG |
| BricsCAD Shape | Windows, macOS | Yes | Free modeler that opens and saves DWG |
| FreeCAD | Windows, macOS, Linux | Via ODA File Converter | Imports DWG only after you install the converter and point FreeCAD to it |
| LibreCAD | Windows, macOS, Linux | No, DXF only | Convert DWG to DXF first |
| QCAD | Windows, macOS, Linux | Professional edition | The community build reads DXF |
| AutoCAD / AutoCAD LT | Windows, macOS | Yes | Full editor, subscription |
If you only need to look, measure and print, a reader is enough. If you need to move lines, you need a CAD editor; see edit DWG online for the realistic options. A fuller comparison lives at best free DWG viewers.
How to view DWG drawings on a phone or tablet
The browser viewer also works on iPhone, iPad and Android for small and medium drawings. Open the site in Safari or Chrome, tap the drop zone, and pick the file from Files or Downloads. Very large DWGs can exhaust a phone's memory, so for a 50 MB site plan use a laptop or a native app.
Autodesk's AutoCAD mobile app opens DWG files on iOS and Android and syncs with Autodesk cloud storage. Platform details are on the iPhone and Android pages.
Why a browser DWG reader keeps the file private
Most online CAD readers upload your drawing to a server, convert it there and send back an image. This one does not. The file is read by JavaScript inside the tab; conversion and rendering happen on your device, and closing the tab removes everything. That matters when the drawing is a client's floor plan or a part you are not allowed to share.
The price of that design is that your machine does the work. A modern laptop handles it easily; an old phone may not.
Opening DWG file problems and fixes
- The file is not a DWG. ZIP archives and PDFs renamed to .dwg are the most common failure. Open the file in a hex or text editor: a real DWG begins with the letters
AC10followed by two digits. - The drawing is R12 or older. Those use the AC1009 format, which LibreDWG reads only partially. Open it in DWG TrueView and save as a newer version.
- The file is over 60 MB. The viewer skips conversion above that size to protect browser memory. Purge and split the drawing first; see open large DWG files.
- Nothing shows after loading. Press fit to view: the saved view may be zoomed on an empty corner. Then check the Layers panel; the content may sit on layers that were turned off when the file was saved.
More causes and the recovery commands are collected in fix a DWG file that will not open.
Frequently asked questions
How do I open a DWG file without AutoCAD?
Drop it into the browser viewer on this page, or install Autodesk DWG TrueView on Windows. Both are free and neither needs AutoCAD. Mac users can use the browser viewer or BricsCAD Shape.
What opens DWG files for free?
The in-browser DWG Viewer, Autodesk DWG TrueView (Windows), Autodesk Viewer online, Bentley View and BricsCAD Shape all open DWG at no cost. LibreCAD does not open DWG directly; it needs a DXF.
How can I read a DWG file on a phone?
Open dwgviewer.app in the phone browser and pick the file; small and medium drawings render fine. For big files or offline work, use Autodesk's AutoCAD mobile app.
How to turn a PDF into a DWG?
Not with a viewer. AutoCAD's PDFIMPORT command converts vector PDFs to DWG geometry; scanned PDFs need raster-to-vector tracing. The options are compared on the PDF to DWG page.
How to open a STEP or STP file in AutoCAD?
Use the IMPORT command in AutoCAD (not LT) and choose the .stp file; it becomes 3D solids you can save as DWG. See STEP to DWG.
Does the viewer upload my drawing?
No. The DWG is parsed, converted and rendered by code running in your browser tab. Nothing leaves the device, and closing the tab removes the file.