Gaphor is a free desktop modeling application for visualizing and documenting applications and systems with UML, SysML, RAAML, and C4. It implements a UML 2 data model and the UML, SysML, and RAAML OMG standards, and supports C4. Diagram choices include Class, Interaction, State Machine, Block Definition, and Requirements; users can mix diagram items and apply custom styling through the built-in engine. Diagrams export as SVG, PNG, PDF, or EPS, and models can be batch-exported. Gaphor can also produce a self-contained, static, interactive, read-only HTML report that can be viewed without a server or backend. As a Python library, it can inspect, generate, or update models through scripts or Jupyter notebooks. A Sphinx extension embeds diagrams in reStructuredText or Markdown documentation. Gaphor is open source under the Apache 2 license and runs on Windows, macOS, and Linux. Windows options include an installer, portable version, or Winget; macOS 10.15 or newer is required. Linux options include Flatpak, Arch, and Debian/Ubuntu packages.
Who it is for
Gaphor suits people who need to model applications or systems using UML, SysML, RAAML, or C4. Its scripting, reporting, and Sphinx support also suit users incorporating models into documentation workflows.
What is good
- Supports UML, SysML, RAAML, and C4
- Exports diagrams to SVG, PNG, PDF, or EPS
- Generates standalone interactive HTML model reports
- Usable as a Python library with Jupyter notebooks
- Available on Windows, macOS, and Linux
What to know first
- macOS 10.15 or newer is required
- Community contact and issue reporting are through Matrix and GitHub
Verdict
Gaphor combines standards-based modeling with diagram exports, HTML reports, and Python scripting. It is free and cross-platform, with macOS 10.15 or newer required.
Gaphor plans and pricing
All plansCompared on UML modeling software
- Free plan
- Yes
- UML diagram types
- Class, Component, Action, Sequence, Interaction, State Machine, Use Case, Deployment, Information Flow
- Code generation
- Yes
- Team collaboration
- Yes
- Deployment
- desktop
- Supported platforms
- Windows, macOS, Linux
- Model repository
- Yes
