How do I open a DWG file without AutoCAD?

Use Autodesk's own free DWG viewer, which is the most accurate option, or their free web viewer if you would rather install nothing. For free 2D editing, LibreCAD works, best via DXF.

What is the difference between DWG and DXF?

DWG is AutoCAD's proprietary native format. DXF is the openly documented interchange format Autodesk publishes so other software can read the drawing. For sharing outside AutoCAD, DXF is the safer choice.

File extensions

How to open a .dwg file

AutoCAD drawing · CAD

A .dwg file is an AutoCAD drawing. Autodesk publishes a free official viewer, and LibreCAD or the free web viewer will open one without a licence. Editing it properly still needs real CAD software.

What a .dwg file actually is

DWG is Autodesk's native format for 2D and 3D drawings, in use since 1982. It stores geometry, layers, blocks and metadata as precise vectors rather than an image.

The format is proprietary and undocumented, which is why third-party support is reverse-engineered and why fidelity varies between the tool that made the file and the tool that reads it.

Why it will not open

Nothing on Windows or macOS opens DWG out of the box, and full AutoCAD is an expensive subscription. Free viewers exist and are perfectly good for reading, but they are not linked from anywhere obvious.

Renaming it to an extension you can open will not help: changing the extension does not convert the file, it only changes what Windows tries to open it with.

Step by step

Windows

01To view and measure: install Autodesk's free DWG viewer, which is the most faithful option because it comes from the vendor.
02To view in a browser with nothing installed, Autodesk also runs a free web viewer that accepts a DWG upload.
03To edit for free: LibreCAD handles 2D drawings well. It works via DXF, so convert or export first for the cleanest result.
04If the drawing was saved in a much newer AutoCAD version than your tool supports, ask for it re-saved to an older DWG version or exported to DXF.

macOS

01The free Autodesk viewer has a macOS build, and the web viewer works in any browser.
02LibreCAD also runs on macOS for 2D editing.

What usually goes wrong

DXF is the interchange format

If you need a drawing to open reliably in something other than AutoCAD, ask for DXF. Autodesk documents it publicly, so support across other CAD tools is far better than for DWG.

Programs that open .dwg

Our pick, in order. Every one links to the publisher's official download URL and the SHA-256 hash of the installer. Once you have downloaded it, you can check the file against our index before you run it.

If you end up downloading one of these from somewhere other than the publisher, what you can and cannot verify about that is worth two minutes.

LibreOfficeLibreOffice is a free and powerful office suite, and a successor to OpenOffice.org (commonly known as OpenOffice). Its clean interface and feature-rich tools help you unleash your creativity and enhance your productivity.v26.2.5.2 · 3 hashed installers100

Also registers .dwg in its manifest

Taken straight from publisher manifests. Some of these handle the format for a narrow purpose rather than as their main job.

XnView MPv1.11.5.0 · 2 hashed installers100

Common questions

How do I open a DWG file without AutoCAD?: Use Autodesk's own free DWG viewer, which is the most accurate option, or their free web viewer if you would rather install nothing. For free 2D editing, LibreCAD works, best via DXF.
What is the difference between DWG and DXF?: DWG is AutoCAD's proprietary native format. DXF is the openly documented interchange format Autodesk publishes so other software can read the drawing. For sharing outside AutoCAD, DXF is the safer choice.