What is a .dxf file?
Drawing Exchange Format · 3D model · Autodesk · 1982
DXF is Autodesk's open interchange format for CAD drawings. It carries the same vector geometry as DWG but in a documented, text-friendly form, so it is the reliable way to move designs between different CAD programs.
What is a .dxf file used for?
DXF was created so CAD data could move between AutoCAD and other software. Its structure is published, and the ASCII variant is even human readable.
It preserves layers, lines, arcs, text and other 2D and 3D entities, making it the common ground when two people use different CAD tools.
It is also widely accepted by laser cutters, CNC machines and vector tools that need precise paths.
DXF comes in two flavours that hold the same geometry: a human-readable ASCII form you can open in a text editor, and a more compact binary form. Like DWG, it is versioned by AutoCAD release, so if an older program rejects a DXF, re-exporting it to an earlier version usually fixes it.
How to open a .dxf file
The .dxf format opens in the following apps, grouped by operating system. If one app does not work, try another from the same list. For a step-by-step walkthrough, see how to open a .dxf file.
Windows
- AutoCAD
- LibreCAD
- Inkscape
- DWG TrueView
macOS
- LibreCAD
- AutoCAD
- Inkscape
Linux
- LibreCAD
- Inkscape
- FreeCAD
Web
- Online CAD and DXF viewers
How to convert a .dxf file
You can convert a .dxf file to DWG, SVG, PDF using a conversion tool or the export menu of an app that opens it.
.dxf file signature (magic bytes)
Programs recognise a .dxf file by the bytes at the start of the file, not by its name. These are the signatures for DXF.
| Hex signature | Offset | Note |
|---|---|---|
| 30 0D 0A 53 45 43 54 49 4F 4E | 0 | text DXF often begins with a section marker |
See the full magic-numbers reference for every format.
Frequently asked questions
What is a .dxf file?
DXF is Autodesk's open interchange format for CAD drawings. It carries the same vector geometry as DWG but in a documented, text-friendly form, so it is the reliable way to move designs between different CAD programs.
Can I open a DXF in Illustrator or Inkscape?
Yes. Both import DXF as vector paths, which is handy for turning CAD drawings into artwork or cut files.
Why does my DXF open at the wrong size?
DXF does not always record its drawing units, so the importing program may guess millimetres for inches or vice versa. Check the unit setting when you import, or scale the drawing to match, especially before laser cutting or CNC.
Related formats
Sources
Details on this page were checked against authoritative references: