PlantUML Editor
PlantUML Online
Edit PlantUML in the browser with live preview. Use this when the PlantUML source is your source of truth. Start from the sample, then export PNG or SVG when the diagram looks right.
Features
- Live editor for plantuml online
- Starter template included on the page
- PNG and SVG export
- No install required
Need a blank canvas? Open the full UML studio.
What you can model
PlantUML covers common UML views and several related diagram types in one text syntax. This online editor is for everyday drafting when you want versionable diagram source without a local install.
How to use this editor
Write an @startuml block, preview on the right, export PNG or SVG, and store the source in git. Open a type-specific maker when you want a guided starter for class, sequence, activity, or ER diagrams.
Notation that matters
Every diagram starts with @startuml and ends with @enduml. Diagram kind is implied by the keywords you use (class, participant, usecase, entity, and so on). Keep themes simple for documentation embeds.
Keep the diagram readable
Need a full-height workspace? Open the studio. Prefer a focused maker when you are learning a specific diagram type. Split large systems across multiple source files or pages instead of one crowded canvas.
Frequently asked questions
Is PlantUML online free here?
Yes. Edit and export in the browser without a paid plan.
Do I need Java installed?
Not for this online editor. Diagrams render through the PlantUML service used by the preview.
Which diagram types work?
Common UML types such as sequence, class, activity, use case, state, component, and deployment, plus related views PlantUML supports.
Related tools
- Class Diagram MakerBuild a UML class diagram in your browser. Start from the template, rename types to match your domai…
- Sequence Diagram MakerDraw a sequence diagram for auth flows, service calls, and feature interactions. Start from the temp…
- Activity Diagram MakerMap a workflow with actions, decisions, and end states. Start from the template, rename steps to mat…
- ER Diagram MakerDesign an entity-relationship diagram for tables, keys, and cardinalities. Start from the template f…
Browse the full UML diagram tools directory or return to the UML diagram hub.