https://www.planttext.com/
PlantUML Editor Online - Free & Fast UML Diagram Tool | PlantText
PlantText is the fastest online PlantUML editor. Write UML diagrams as code and instantly generate class, sequence, activity, and state diagrams. No...
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https://miro.com/diagramming/uml-diagram/
FREE UML Diagram Tool Online | Miro
Use Miro's intuitive UML diagram tool to map out complex systems. Build diagrams with UML symbols and easily collaborate online.
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