What is a CAD macro?
A macro is a small script that automates a sequence of actions inside the CAD application. Examples are SOLIDWORKS VBA macros (.swp), CATIA VBA / CATScript macros, AutoCAD scripts (.scr) and AutoLISP routines, and Inventor iLogic rules. Macros are quick to write and great for personal or team shortcuts.
Limitations: basic user interfaces, harder to manage across many users, limited error handling and often tied to one engineer who wrote them.
What is a CAD add-in?
An add-in is a compiled program (usually .NET or C++) that the CAD application loads at start-up. It can add ribbon tabs, dockable panels, event handlers and connections to databases or web services. SOLIDWORKS, Inventor and Revit all use the term "add-in" officially.
Strengths: professional UI, better performance, proper installers, version control and full access to the API.
What is a plugin?
Plugin is the general industry word for any software component that extends a host application. In practice, "plugin" and "add-in" usually describe the same thing. Autodesk App Store products for AutoCAD are commonly called plugins, while the same technology in Inventor is called an add-in.
Side-by-side comparison
| Macro | Add-in / Plugin | |
|---|---|---|
| Languages | VBA, AutoLISP, iLogic, scripts | C#, VB.NET, C++, Python |
| Development time | Hours to days | Days to months |
| User interface | Simple forms or none | Ribbon, palettes, rich dialogs |
| Performance | Good for small tasks | Suitable for large models and batches |
| Deployment | Copy files, manual setup | Installer, auto-load, updates |
| Integration | Limited | Databases, ERP, PLM, web APIs |
| Best for | Personal or small-team shortcuts | Company-wide tools and products |
How to choose
- Choose a macro when the task is simple, used by a few people and you need it this week.
- Choose an add-in when many users depend on it, it needs a proper UI, it touches other systems, or it must be reliable for years.
- Upgrade a macro to an add-in when it becomes business-critical or the original author is leaving.
Many successful add-ins started life as a macro that proved the idea. That is a perfectly good path.
Macro or add-in, we can help
ENGIMANDI writes quick macros and full add-ins, and converts fragile macros into maintainable software for SolidWorks, CATIA, AutoCAD and Inventor.