The best free alternative to IBM Rational Software Architect is Umbrello, which is also Open Source. If that doesn't suit you, our users have ranked more than 10 alternatives to IBM Rational Software Architect and seven of them is free so hopefully you can find a suitable replacement. Other interesting free alternatives to IBM Rational Software Architect are ClickCharts, UMLet, Papyrus UML and Dynamic Draw.
Umbrello is a Unified Modelling Language (UML) modelling tool and code generator. It can create diagrams of software and other systems in the industry-standard UML format, and can also generate code from UML diagrams in a variety of programming languages.
Design flowcharts, UML, Venn, and mind map diagrams with customizable templates, varied symbols, shapes, connector styles, overlapping sheet support, and intuitive drag-and-drop editing. Export visuals as images, edit multiple diagrams, and organize complex data visibly.
UMLet is an open-source UML tool with a simple user interface: draw UML diagrams fast, export diagrams to eps, pdf, jpg, svg, and clipboard, share diagrams using Eclipse, and create new, custom UML elements.
A Powerful idea processor.It's Open Source and Freeware. Create UML Diagrams, Network Diagrams, Flowcharts and many other types of diagrams with the versatile Dynamic Draw Software.
Open source tool that provides methodological guidance, intuitive model editing, and viewing capabilities for Systems, Software and Hardware Architects.
The Model Development Tools (MDT) project focuses on big "M" modeling within the Modeling project. Its purpose is twofold:
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It's Free and based on Eclipse environment.