.dwg.dxf
DWG and DXF files: what they are and how to open them
A DWG is an AutoCAD drawing and a DXF is its exchange copy. Universal File Opener on Android and Windows draws a DXF’s 2D geometry and shows a DWG’s saved preview picture. A full DWG needs CAD software or a DXF export.
Check your DWG and DXF file here
Nothing is uploaded. This page names the type and shows its details; to view it, use an app below.
What is a DWG and DXF file?
DWG is Autodesk’s native drawing format for AutoCAD: floor plans, parts and site layouts. DXF is Autodesk’s documented exchange format, made for passing drawings between programs, so far more free tools can draw it.
DWG is proprietary, and its format changes every few AutoCAD releases; the current one dates from AutoCAD 2018. That is why many apps cannot draw one. When a DWG will not open, saving a DXF from CAD software is the usual route.
Our apps show a DWG’s saved preview picture and version, not the drawing itself. For a DXF they draw the model, with pan, zoom, layer switches and distance measuring. Saving SVG, PNG or PDF copies needs Pro.
What is inside
A DWG begins with a version tag: AC1015 is AutoCAD 2000, AC1018 is 2004, AC1021 is 2007, AC1024 is 2010, AC1027 is 2013 and AC1032 is 2018 and later. A header directory can point to a thumbnail saved as BMP, PNG or WMF so file browsers can show the drawing. The app shows that thumbnail.
A DXF is text, or a binary form of it, made of pairs: a numeric group code, then its value. Sections hold settings, layers, reusable blocks and the entities themselves. The apps draw lines, arcs, circles, polylines, splines, text, hatches and dimensions in 2D. 3D solids and meshes are left out, and other 3D geometry is projected flat.
plan.dxf 0 SECTION / 2 HEADERunits and drawing settings 0 SECTION / 2 TABLESlayers and line types 0 SECTION / 2 BLOCKSreusable symbols 0 SECTION / 2 ENTITIESlines, arcs, text and more 0 EOFHow to open a DWG and DXF file
Windows
- Autodesk DWG TrueViewFree viewer from Autodesk for DWG and DXF drawings. Windows only.
- Universal File Opener for WindowsOursDraws a DXF offline with its layers and measures distances. For a DWG it shows the saved preview. Read only.
Mac
- AutoCAD for MacPaid. Opens and edits DWG and DXF drawings.
- LibreCADFree. Draws DXF files in 2D; use it after saving a DXF from CAD software.
Android
- AutoCADAutodesk’s app opens DWG drawings. After a 30 day free trial it keeps limited read only use; editing needs a subscription.
- Universal File OpenerOursDraws a DXF offline with layers and measuring, and shows a DWG’s saved preview. Free to open and read only.
In a browser
- Autodesk ViewerFree with an Autodesk account. Opens DWG and DXF online, but you upload the file to Autodesk’s servers.
Won’t open?
A DWG shows only a small picture
Universal File Opener shows the preview saved inside a DWG and does not read its drawing. Ask for a DXF or PDF, or open the DWG in DWG TrueView or AutoCAD.
A DWG has no preview at all
The program that saved it may have left the thumbnail out. The app says so. Use DWG TrueView or ask for a DXF export.
AutoCAD says the DWG is from a newer version
Older AutoCAD cannot read newer drawings. Open it in the current DWG TrueView, which can also convert it to an earlier version, or ask the sender to save it in an older DWG format.
Text, hatches or dimensions look off in a DXF
Fonts map to system fonts, so SHX shapes and some text formatting differ. Some hatch patterns and dimensions are approximated, and unsupported entities are left out with a notice.
A 3D drawing looks flat
The apps draw 2D geometry. 3D solids and meshes are left out, and other 3D geometry is projected flat.
A large DXF stops partway
Files over 32 MiB are refused, and reading stops after five seconds with a notice and the part drawn so far.
Convert a DWG and DXF file
- To SVG, PNG or PDFOpen a DXF in Universal File Opener and use Convert; saving the copy needs Pro. PDF export stops if the drawing has text the bundled font lacks.
- To DXF from a DWGIn AutoCAD choose Save As and pick a DXF type. Universal File Opener cannot convert a DWG.
DWG and DXF files in our apps
Universal File Opener draws DXF drawings in 2D offline on Android and Windows, with layers and distance measuring, and saves SVG, PNG or PDF copies with Pro. For a DWG it shows the saved preview picture and version, not the drawing.
All Android tools and limits for DWG and DXF files
- DXF R12 through 2018, ASCII and binary: draws 2D geometry, text, layers, hatches and blocks, with pan, zoom, layer switches and distance measuring.
Limits
- DWG shows only its saved BMP, PNG or WMF preview. The drawing is not decoded; export a DXF from CAD software for geometry.
- 3D solids and meshes are left out, and other 3D geometry is projected flat. Paper-space layouts may be missing or incomplete, with a notice.
- Read only. Files over 32 MiB are refused.