CGCADGuide.tools
Free Utility

AutoCAD DWG Version Checker

Struggling to open a drawing file? Drag and drop your `.dwg` file here to instantly identify its internal release version and check software compatibility without uploading.

Drag & Drop your DWG file here

Or browse files on your device. Processing is 100% local — your data never leaves your browser.

Pure client-side WebAssembly / JS

Manual Code Explorer

No drawing file handy? Manually inspect any DWG header code to test its cross-platform CAD software support matrix.

DWG Version Compatibility FAQ

What is a DWG magic header code?

Every DWG file begins with a 6-byte ascii code (e.g. AC1032) indicating the format database version it was written in. The CAD program reads this code first to decide whether it can unpack the vector data.

Why can't my AutoCAD open a newer DWG?

Autodesk AutoCAD is not forward-compatible. If you run AutoCAD 2017 (AC1027), you cannot open a DWG saved in AutoCAD 2018 format (AC1032). You must convert it using a newer viewer or an alternative CAD tool.

Are alternative CAD tools 100% compatible?

Modern IntelliCAD and ODA-based engines (GstarCAD, ZWCAD, etc.) are native DWG systems. They can read and write standard DWG formats directly without conversion, matching Autodesk's structural fidelity.

Is my file safe when dragging into this page?

Yes, absolutely. We only use the local HTML5 FileReader API to read the first 6 characters in your browser. The file is never uploaded to any remote server or third-party database.