A complete, cost-free UML tool

Beginners, students, and other non-commercial users will find Poseidon for UML to be a thorough UML tool without the limits imposed by the community versions of other tools. It contains all 9 UML diagrams and all implemented diagram elements. You can create, save, and load projects, browse existing models, exchange models, generate Java code, export your diagrams to various formats, and much more.

The Poseidon difference

Other tools claim to be intuitive, but their interfaces are overly complex and can be intimidating for new users. Poseidon for UML has an inherent simplicity that lets you create models with ease. Download the Community Edition of Poseidon for UML and see the Poseidon difference for yourself.


  • Fully implemented in Java, platform independent
  • Supports all 9 diagrams of the UML
  • Saving format compliant to the UML 2.0 Diagram Interchange Standard
  • Supports XMI 1.2 as the standard saving format. XMI 1.0, 1.1 and 1.2 can be loaded
  • Advanced printing options
  • Supports graphic formats gif, ps, eps, svg, jpg, and png
  • Internationalization and localization for English, German, Russian, French, Spanish, and Chinese
  • Code generation for Java
  • Simple installation and updates with Java Web Start

URL: http://www.gentleware.com
Licence: Proprietary