Drawuml — build PlantUML diagrams visually

Drawuml is a free, browser-based visual editor for PlantUML UML diagrams — class, object, use case, component, deployment and state diagrams. Drag shapes onto the canvas and the PlantUML code writes itself; edit the code and the diagram follows. The sync runs both ways, and your layout is preserved. No account, no backend, no PlantUML server: diagrams are rendered and saved in your own browser.

• Class diagrams: classes, interfaces, enums, abstract classes and annotations, with typed members, visibility markers and stereotypes.
• Object diagrams: objects with field = value rows, and map tables.
• Use case diagrams: actors, use cases and boundary rectangles.
• Component diagrams: components, interfaces, databases, clouds, nodes and packages.
• Deployment diagrams: nodes nested as deep as you like, with artifacts, stacks, hexagons and processes.
• State diagrams: states and descriptions, composite states, start and end markers, choice, fork and join.
• Sequence diagrams: participants, messages, activations, notes and alt/loop blocks, on a board where the code order is the drawing.
• Every UML relationship: extension, realization, composition, aggregation, association, dependency and plain links, with cardinalities.
• Live PlantUML code with two-way sync, and one-click copy.
• Export to PlantUML, SVG, PNG or PDF; share diagrams as links.
• Version history with restore and visual diffs, plus light and dark themes.