Complex PlantUML diagrams that stay easy to edit

Copy & paste your PlantUML into a fenced Markdown block (meaning just ```plantuml) and Notes Plus renders the diagram right beside it. Document systems, workflows, and ideas with diagrams that remain portable, reviewable, and part of the note.

Roadmap End of 2026: Create and edit PlantUML diagrams directly in the visual editor without touching code

Apple Silicon v0.3 Intel Mac v0.3

Notes Plus showing PlantUML source in a split editor alongside a rendered Notes Platform Architecture diagram.

Notes Plus displaying a rendered PlantUML Notes Platform Architecture diagram in the visual editor.

PlantUML is a text language for technical diagrams. This small example is a sequence diagram: each arrow represents a message between participants, making it useful for documenting interactions and user flows.

Use a plantuml fenced block, begin with @startuml, write the diagram statements, and close with @enduml. For example, Alice -> Bob: Hello draws a request and Bob --> Alice: Hi draws a return message. Visual mode renders the result; raw mode exposes the source. The PlantUML language guide has syntax and examples.

Notes Plus showing a small PlantUML sequence diagram between Alice and Bob in the visual editor.