This foremost open-source UML modeling tool supports all standard UML 1.4 diagrams. It operates on any Java platform and is accessible in ten languages and is distributed under the Eclipse Public License (EPL) 1.0. It is not only a free UML modeling tool, but also an open-source development project that fosters collaboration and innovation.

ArgoUML is the leading open source UML modeling tool and includes support for all standard UML 1.4 diagrams. It runs on any Java platform and is available in ten languages.
ArgoUML is distributed under the Eclipse Public License (EPL) 1.0.

ArgoUML is an open source project. The availability of the source ensures that a new generation of software designers and researchers now have a proven framework from which they can drive the development and evolution of CASE tool technologies.

ArgoUML is not only a free UML modelling tool, it is also an Open Source Development project where you are invited to contribute.