The best open source alternative to StarUML is PlantUML. If that doesn't suit you, our users have ranked more than 50 alternatives to StarUML and many of them is open source so hopefully you can find a suitable replacement. Other interesting open source alternatives to StarUML are Mermaid, quiver diagram editor, Umbrello and Modelio.
PlantUML is an open-source tool that uses simple textual descriptions to draw UML diagrams. The generator can be run anywhere within JVM and integrated with various application such as wiki, text editor, IDE, programming language, documentation generator, and others.
Ever wanted to simplify documentation and avoid heavy tools like Visio when explaining your code? This is why mermaid was born, a simple markdown-like script language for generating flowcharts, Gantt charts and sequence diagrams from text via JavaScript.
Efficient web-based tool for constructing high-quality commutative diagrams. Offers LaTeX export with embedded links, intuitive interface supporting both mouse and keyboard inputs, and features like multiple selections, macro support, and smart label alignment.
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.
Modelio is an open source modeling tool supporting natively UML, BPMN and model exchange with XMI. It allows to draw all UML2 diagrams and specific diagrams for business process modeling. It is easy and powerful with the capacity to add new functionalities to the application.
UML Designer provides a set of common diagrams to work with UML 2.5 models. The intent is to provide an easy way to make the transition from UML to domain specific modeling.
Open source tool that provides methodological guidance, intuitive model editing, and viewing capabilities for Systems, Software and Hardware Architects.
WhiteStarUML is a fork of StarUML with an intent to revive its Delphi code base by updating code to recent Delphi editions, reducing dependence on third party components and fixing bugs and adding new features.
The Model Development Tools (MDT) project focuses on big "M" modeling within the Modeling project. Its purpose is twofold:
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.
NClass is a free tool to easily create UML class diagrams with full C# and Java language support. The user interface is designed to be simple and user-friendly for easy and fast development. Properties, enums, delegates and other language specific elements are fully supported...
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