This is the place to come if you want to have a deeper insight into FreeCAD. Here you can learn about customizing FreeCAD for your needs.

These pages are in early stage of development. If you can't find the information you are looking for, or have found useful information somewhere we have not linked to, then please leave a comment on the forum, or, why not? Add some more content here yourself!

One of the nicest features of FreeCAD is that you can script and extend it extremely far without the need to compile anything or touch the source code. All the scripting part is done in Python, a very powerful but simple programming language. With simple Python scripts, you have total access to about any part of FreeCAD. For example, you can:

  • Create and modify geometry: Is there a special object you need that's not present in the default FreeCAD installation? You can easily create a new object type, either from scratch or by adapting an existing type.
  • Create custom tools and commands: At the moment, FreeCAD already has extensive functionality, but there aren't many convenient tools and commands for the final user yet. But it is already easy to create your own sets of tools.
  • Modify the interface: The FreeCAD user interface is still very basic at this stage. But everything is there for you to extend it to your needs. You can, for example, create toolbars to put your own tools, create special panels for interacting with your tools, etc.
  • Modify the scene representation: FreeCAD has separate processes for building up and computing the geometry and displaying that geometry on your screen. You have full access to the way the scene contents are displayed on screen, therefore you can modify that representation, interact with it, or add all kinds of custom behaviours and screen widgets, like information, draggers, anchors or temporary entities.

Customizing FreeCAD

Scripting in FreeCAD



As the functionality of FreeCAD is separated in Modules which deal with special data types and applications. FreeCAD has built-in modules and Extension Modules (plug-ins). Once plugin modules are installed, they become availible to you as easily as the built-in modules. The modules described below are the default modules, includeed in every FreeCAD installation.

  • The Builtin modules are the principal FreeCAD modules. They contain tools for manipulating general FreeCAD configurations, documents and their contents.
  • Workbench creation shows you how to create your own workbench

Working with Meshes

Working with Parts

Accessing the Coin scenegraph

Controlling the Qt interface

Working with parametric objects


  • Code snippets : A collection of pieces of FreeCAD Python code, to serve as ingredients in your scripts...
  • Line drawing function: How to build a simple tool to draw lines
  • Dialog creation: How to construct dialogs with Qt designer, and use them in FreeCAD
  • Embedding FreeCAD: How to import FreeCAD as a Python module in other applications
  • The Draft Module adds basic 2d drawing functions to freecad. It is written entirely in Python, so it can be a good example if you want to write your own modules.
  • FreeCAD vector math library : A couple of handy functions to manipulate FreeCAD vectors. This library is also included in the Draft module.

API Functions

The complete API documentation of FreeCAD is located at http://www.freecadweb.org/api/ . It contains both C++ and Python APIs, and is not totally well formatted yet, which can be confusing when looking for python-only code. An easier to browse version can be found here. Note that it can be incomplete, since it is updated manually. For more accurate information, browse the modules directly from FreeCAD's Python console.

Advanced modification

Python tutorials

These are good generic tutorials, not specific to FreeCAD, that might interest you if you are totally new to python.


PySide - How to create and manage FreeCAD's Qt UI interface from python

The following two references are PyQt specific (not PySide) but may offer some information of use:

Pivy - How to interact with FreeCAD's 3D scenes

Community projects

On the Community portal, you can find other FreeCAD-based projects run by the FreeCAD users community. If you are starting a new FreeCAD project, be sure to list it there! We also have a page with things you can do if you would like to Help FreeCAD.

Other languages:
čeština • ‎Deutsch • ‎English • ‎español • ‎français • ‎Bahasa Indonesia • ‎italiano • ‎polski • ‎português • ‎português do Brasil • ‎română • ‎русский • ‎svenska • ‎中文(台灣)‎