Altova UModel vs Gaphor
Altova UModel
altova.comGaphor
gaphor.orgSide by side
| Figure | Altova UModel | Gaphor |
|---|---|---|
| Price from | — | Free |
| Free plan | — | Yes |
| Free trial | Yes | — |
| Open source | — | — |
| Windows | Yes | Yes |
| macOS | — | Yes |
| Linux | — | Yes |
| Plans published | 3 | 1 |
| Spec score · UML Modeling Software | 8.2 (#4) | 7.8 (#13) |
| Purpose | UModel is a visual UML software modeling tool that can generate source code and project documentation or reverse engineer existing programs into UML diagrams. | Gaphor is a modeling application for UML, SysML, RAAML, and C4 used to visualize and document applications and systems. |
| Support | Altova provides a technical support form and lists online training among its support resources. | The project provides community contact through Matrix chat and accepts issue reports through GitHub. |
Plans
Altova UModel
- UModel 2026 Basic Edition$209, paid once
- UModel 2026 Professional Edition$349, paid once
- UModel 2026 Enterprise Edition$429, paid once
In their own words
Altova UModel
Altova UModel has no write-up on Specifiction yet; its figures are above.
Gaphor
Gaphor is a 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 the C4 model. Its diagram options include Class, Interaction, State Machine, Block Definition, and Requirements diagrams, with diagram items that can be mixed and styled through a built-in engine. Diagrams export to SVG, PNG, PDF, or EPS, including batch export for every diagram in a model. Gaphor can also create a static, interactive, read-only HTML model report that needs no 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. The software is free under the Apache 2 license for Windows, macOS, and Linux. Windows users have installer, portable, and Winget options; macOS requires version 10.15 or newer.