Gaphor is a UML, SysML, RAAML, and C4 modeling application. It is designed to be easy to use, while still being powerful. Gaphor implements a fully-compliant UML 2 data model, so it is much more than a picture drawing tool. You can use Gaphor to quickly visualize different aspects of a system as well as create complete, highly complex models.

Multi-platform

Gaphor works on all major platforms: Windows, macOS, and Linux.

Open Source

No vendor lock-in: Gaphor is written in Python and is 100% Open Source, available under a friendly Apache 2 license.

Beginner or Pro

Whether you’re a casual modeler documenting a project or a Model Driven Development expert, Gaphor has got you covered.

Consistent

UML is a graphical modeling language, so all information you put in the model is visible in the diagrams. For example, stereotypes are modeled in diagrams. No hidden panels and property pages. Just diagrams!

Extensible

Gaphor is extensible. Plug-in a code generator or export your diagrams for documentation. Create your own extensions and access them through the GUI or CLI.

Standards Compliant

Gaphor implements the UML, SysML, and RAAML OMG standards. It also includes support for the C4 model for visualizing software architectures.