DWG vs DXF

What each file is, which one is smaller, and which one to send.

Updated 22 October 2026

DWG is the file AutoCAD works in. DXF is the same drawing written out as text, so almost any CAD, laser or CNC program can read it. A text DXF is usually three to four times the size of its DWG.

3.7× median size of a text DXF next to its DWG, in 130 test drawings

25% what a binary DXF saves over a text DXF, per Autodesk

3D solids, regions and bodies travel in both files

Convert a DWG to DXF Free, in your browser, and the drawing stays on your device

Compared	DWG	DXF
What it is	AutoCAD's own drawing file	A text copy of the drawing, made for other programs
Who reads it	AutoCAD and DWG-compatible CAD programs	Nearly every CAD, CAM, laser and CNC program
Size	Smaller	About 3 to 4 times larger as text
3D solids	Yes	Yes
Versions	Yes: a newer DWG may not open in an older program	Yes: a newer DXF may not open in an older program

Which is smaller, DWG or DXF?

DWG. It stores the drawing in a compact binary form, while a text DXF spells out every value as readable characters.

We saved 130 test drawings, from AutoCAD R13 to 2018, as text DXF with the ODA File Converter. The DXF came out a median 3.7 times the size of its DWG, and only one of the 130 was smaller.

The "DWG is 25% smaller" line on many pages comes from a different comparison. Autodesk's DXF reference says a binary DXF takes about 25 percent less space than a text DXF, and AutoCAD reads it about five times faster.

Can a DXF file hold 3D?

Yes. Autodesk describes the text DXF as a complete representation of an AutoCAD drawing, and 3D solids, regions and bodies are stored inside it as ACIS data.

Whether the 3D comes through depends on the program that opens the DXF. A solid that looks right in one CAD program may be skipped by a program that only reads flat lines.

Which one should I send?

To someone on AutoCAD: send the DWG. If their AutoCAD is older than yours, save it in their version first.
To a laser, CNC or plasma shop: send a DXF, and ask which DXF version their software reads.
To someone on another CAD program: many of them open DWG too, so try the DWG and send a DXF if it does not open.

Which DXF version should I pick?

A DXF has versions just like a DWG, and the 2018 format is the newest. An older program may refuse a newer file, and some cutting software only reads R12 or 2000, so ask the shop and pick the version they name.

Our DWG to DXF converter writes DXF 2018 down to 2000. It does not write R12 yet.

What can change when a DWG becomes a DXF?

Lines, arcs, text, dimensions, layers, blocks and layouts come through. What can stop working is the behaviour only AutoCAD understands.

When we saved a drawing with dynamic blocks as DXF with the ODA File Converter, their grips, parameters and actions, and the drawing's geometric constraints, were written as proxy objects. The blocks keep the shape they had when the file was saved, but only a program that knows those objects can change them with their grips again.

Questions

Can you convert a DWG to a DXF file?

Yes. In AutoCAD, use Save As and pick a DXF type. Without AutoCAD, our free DWG to DXF converter does it in your browser, without uploading the drawing.

Is an AutoCAD file DWG or DXF?

AutoCAD saves drawings as DWG. It opens and saves DXF too, which is how drawings move to other programs.

What program opens a DWG without AutoCAD?

Autodesk's free DWG TrueView and Autodesk Viewer both open DWG files. Many other CAD programs open them too.

Sources

Autodesk, DXF Reference (AutoCAD 2012), "Binary DXF Files", page 234
Autodesk, free viewers: DWG TrueView and Autodesk Viewer
FormatYard test set: 130 drawings from AutoCAD R13 to 2018, saved as text DXF 2018 with the ODA File Converter, October 2026