What is DWG?
DWG is the native binary format for AutoCAD - the dominant CAD (Computer-Aided Design) software. Contains 2D/3D geometric data (lines, arcs, polylines, 3D meshes), layers, blocks (reusable symbols), dimensions, annotations, layouts, and metadata. Binary format with proprietary encoding, changing with each AutoCAD version (DWG 2000, 2004, 2007, 2010, 2013, 2018, etc.). Backward compatibility often limited. Compressed internal structure for efficiency.
DWG is the universal language of architecture, engineering, and construction (AEC) industries. Architects design buildings, engineers create mechanical parts, civil engineers draft infrastructure - all in DWG. Virtually every CAD software supports DWG import/export due to market dominance: BricsCAD, DraftSight, LibreCAD, FreeCAD, QCAD. Autodesk defends proprietary format despite calls for openness. Open Design Alliance (ODA) provides libraries for third-party DWG support. DXF (Drawing Exchange Format) is ASCII-based alternative for interchange, but DWG remains primary working format.
History
Autodesk created DWG as AutoCAD's native format in 1982, establishing it as the global standard for technical drawings in architecture, engineering, and construction.
Key Milestones
- 1982: AutoCAD 1.0 with DWG
- 1990s: Industry standard adoption
- 1998: Open Design Alliance (ODA) formed
- 2006: Autodesk sued over format control
- 2010: 3D modeling features expanded
- Present: Dominant CAD format worldwide
Key Features
Core Capabilities
- 2D Drafting: Lines, arcs, polylines
- 3D Modeling: Meshes, solids, surfaces
- Layers: Organized drawing structure
- Blocks: Reusable symbols
- Dimensions: Precise measurements
- Layouts: Multiple views, plotting
Common Use Cases
Architecture
Building designs, floor plans
Engineering
Mechanical parts, schematics
Civil
Infrastructure, site plans
Manufacturing
Product design, tooling
Advantages
- Industry standard (universal acceptance)
- Comprehensive 2D/3D capabilities
- Precise technical drawing tools
- Extensive software support (AutoCAD + alternatives)
- Rich metadata and annotation support
- Decades of established workflows
- Professional AEC ecosystem
Disadvantages
- Proprietary format (Autodesk-controlled)
- Version compatibility challenges
- Expensive AutoCAD software licenses
- Complex format (reverse engineering difficult)
- Limited open-source alternatives
- File corruption risks with large drawings
Technical Information
Format Specifications
| Specification | Details |
|---|---|
| File Extension | .dwg |
| MIME Type | application/acad, image/vnd.dwg |
| Format | Binary (proprietary) |
| Contents | 2D/3D geometry, layers, metadata |
| Versions | Format changes with AutoCAD releases |
| Interchange | DXF (ASCII alternative) |
Common Tools
- Primary: AutoCAD (Autodesk subscription)
- Alternatives: BricsCAD, DraftSight, LibreCAD
- Free Viewers: Autodesk Viewer, DWG TrueView
- Conversion: DXF, PDF, SVG exports