FreeCAD is a parametric 3D modeler made primarily to design real-life objects of any size. Parametric modelingallows you to easily modify your design by going back into your model history and changing its parameters. FreeCAD is open-source and highly customizable, scriptable and extensible.https://www.frecadweb.org
FreeCAD is multiplatfom (Windows, Mac and Linux), and reads and writes many open file formats such as STEP, IGES, STL, SVG, DXF, OBJ, IFC, DAE and many others.
FreeCAD is a very mature and complete tool for 2D and 3D parametric drawing and modelling. Being a free and open-source tool, FreeCAD has not been declared production ready quite yet by the development team. However, FreeCAD can be used in many situations without having to resort to a commercial software package.
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