build123d

Windows · Mac · Linux

Freedom report

Three barsScore 7.0

build123d is ranked #24 of 148 in 3D modeling software on Freedom251. It runs on Linux, macOS, Windows. There is a free plan.

build123d plans and pricing

build123d Free Open-source Python CAD library · install with pip github.com · 30 Sept 2026

Free plan: Yes
Modeling method: parametric
Assembly design: Yes
Sheet-metal tools: Yes
Surface modeling: Yes
Cloud collaboration: No
Supported platforms: Windows, macOS, Linux (Python package)
File import and export: Import: STEP, STL, 3MF; export: BREP, DXF, glTF, OBJ, STL, STEP, SVG, 3MF

Product Type: Python-based parametric BREP modeling framework for 2D and 3D CAD.
Programming Language: Python
Geometry Basis: Boundary representation, or BREP, modeling.
Geometric Kernel: Built on the Open Cascade geometric kernel.
Manufacturing Uses: Suitable for 3D printing, CNC machining, laser cutting, and other manufacturing processes.
CAD Export: Models can be exported to FreeCAD and SolidWorks.
Design Approach: Designed for modern, maintainable CAD-as-code.
Geometry Classes: Provides explicit 1D, 2D, and 3D geometry classes with defined operations.
Extensibility: Supports subclassing and functional composition without monkey patching.
Code Standards: Uses PEP 8, mypy, pylint, and rich Pylance type hints.
Python Integration: Integrates deeply with Python through selectors, locations, and natural conversions.
Algebraic Modeling: Supports operator-driven, readable, composable modeling logic.
Model Complexity: Intricate parametric models can be created in a few lines of readable Python code.
Offline Documentation: Documentation is available in PDF and EPUB formats for offline reference.
Price from: Free

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