What is a DWG file?
A DWG file is a drawing made in AutoCAD or other CAD software. It holds the exact geometry of a plan, a part or a map, plus the sheets set up for printing it.
DWG in short
- Name: short for "drawing".
- Made by: AutoCAD and many other CAD programs that read and write the format.
- Used for: architecture, engineering, construction, surveying, interiors and manufacturing.
- File ending: .dwg. Related files are .dxf (exchange format), .dwt (template) and .bak (backup).
What is inside a DWG
- The model. The drawing itself, at full size: a 30 m building is drawn 30 m long.
- Layouts. Sheets ready for printing, such as an A1 plan with a title block, showing the model through viewports at a scale such as 1:100.
- Layers. Named groups such as walls, doors, dimensions and furniture, which can be shown or hidden.
- Blocks. Reusable symbols such as doors, windows and fittings.
- Lineweights, linetypes and colours, which control how the drawing prints.
- Links to other drawings (xrefs) and images.
How to open a DWG file
You do not need AutoCAD to look at one. The free DWG viewer here opens it in your browser, shows every sheet, and saves it as a PDF, with nothing uploaded. See also how to open a DWG without AutoCAD.
DWG, DXF and PDF
- DWG is compact and is the format the drawing is worked on in.
- DXF is a text-based exchange format that more programs can read. It is often used for laser cutting and CNC.
- PDF is for sharing and printing. Anyone can open it, but it is no longer an editable drawing. See DWG to PDF.
DWG versions
The format has changed many times since the 1980s. A file's version decides which software can open it. See DWG versions explained, or check a file with the version checker.