Open-source Siemens NX alternative

FreeCAD is a parametric 3D modeling application for designing physical objects of any size. Parametric modeling means you can change a design by editing parameters in its model history. It can create 3D shapes from constrained 2D sketches and produce production drawings from the resulting 3D models. FreeCAD is released under the LGPL-2.1 license and written mostly in C++.

The software suits hobbyists, programmers, experienced CAD users, students and teachers working on product design, mechanical engineering and architecture. Related topics on the project include BIM, FEM, CAM, civil engineering and 3D printing. It builds on the OpenCASCADE geometry kernel, the Coin3D scene library, a Qt interface and a broad Python API for scripting. Precompiled packages for Windows, macOS and Linux are available from the releases page, and many Linux distributions include it in their software centers.