Actors and User Goals
Declare actors for people, organizations, or external systems. Write each use case as a goal the actor wants to accomplish, such as Place Order or Approve Refund, instead of naming screens or implementation details.
PlantUML Use Case Diagram Online
Create a PlantUML use case diagram online, connect actors to system capabilities, preview the result, and export PNG or SVG.
PlantUML Use Case Diagram Online Editor
Start with the Use Case Diagram template, edit the PlantUML source, and preview the result live.
Use this focused use case diagram tool for quick previews and exports. Open the full editor for AI generation, syntax repair, sharing, and saved projects.
Diagram preview
Create a PlantUML Use Case Diagram Online
Model actors, use cases, system boundaries, associations, includes, extensions, and generalization in an editable PlantUML workspace with live preview and PNG or SVG export.
Built-in Use Case Diagram template
Start from valid PlantUML source designed for a practical use case diagram.
Live diagram preview
See the rendered diagram update as you edit the PlantUML source.
Focused use case diagram guidance
Learn the syntax and modeling choices used for requirements discovery, product scoping, stakeholder workshops, access analysis, and system boundary documentation.
PNG and SVG export
Download a shareable PNG or scalable SVG from the same source.
No local setup
Create and preview PlantUML without installing Java, Graphviz, or an IDE extension.
Continue in OnUML
Move to the full editor for AI generation, repair, sharing, and saved projects.
How to Create a PlantUML Use Case Diagram
Use the built-in template to create a use case diagram for requirements discovery, product scoping, stakeholder workshops, access analysis, and system boundary documentation.
- 01
Start with the built-in Use Case Diagram template.
- 02
Name each external actor by role rather than by person.
- 03
Place user goals inside a system boundary.
- 04
Connect actors and add include or extend relationships only when they clarify shared behavior.
- 05
Preview and export the use case diagram as PNG or SVG.
PlantUML Use Case Diagram Syntax and Use Cases
Learn the core syntax and modeling decisions behind a useful use case diagram, then apply them directly in the online editor above.
System Boundaries
Group use cases inside a rectangle named after the system or product. Actors normally remain outside the boundary, making it clear which responsibilities belong to the system and which belong to its environment.
Include and Extend
Use <<include>> when one use case always reuses another behavior. Use <<extend>> for conditional or optional behavior. Avoid adding these relationships when a direct actor-to-goal link already communicates enough.
(Checkout) ..> (Authenticate User) : <<include>>
(Apply Coupon) ..> (Checkout) : <<extend>>Use Cases vs User Stories
A use case diagram provides a high-level map of actors and goals. User stories and acceptance criteria describe the detailed behavior behind those goals. Use the diagram for scope and navigation, then link to detailed requirements.
PlantUML Use Case Diagram Example
The editable example demonstrates a practical use case diagram. Change the source, check the live preview, and export the version you need.
@startuml
left to right direction
actor Customer
actor Admin
rectangle "Order System" {
usecase "Place Order"
usecase "Track Order"
usecase "Manage Orders"
}
Customer --> "Place Order"
Customer --> "Track Order"
Admin --> "Manage Orders"
@endumlRelated PlantUML Tools
Use these related tools when you need a different export format or a full PlantUML editing workflow.
PlantUML Tools
Browse the complete OnUML matrix of online PlantUML tools and converters.
View all PlantUML toolsPlantUML Online Editor
Use the general editor when you want to switch freely between diagram types.
Open the general editorPlantUML Sequence Diagram Online
Create and export a focused sequence diagram with a built-in template.
Create a sequence diagramWhy Use PlantUML for Use Case Diagrams
PlantUML keeps use case diagrams in reviewable text, making them easier to update, version, reuse, and export as the design changes.
Start from the right diagram type
Open directly into a Use Case Diagram template instead of adapting an unrelated example.
Keep the model reviewable
Store the diagram as readable text that works well in documentation and version control.
Preview before sharing
Check structure, labels, and relationships before exporting the rendered diagram.
Frequently Asked Questions
What is a PlantUML use case diagram online tool?
It is a browser-based editor that starts with a Use Case Diagram template and lets you edit PlantUML source, preview the rendered diagram, and export PNG or SVG without local setup.
What can I model in a use case diagram?
Use it to model actors, use cases, system boundaries, associations, includes, extensions, and generalization. Common uses include requirements discovery, product scoping, stakeholder workshops, access analysis, and system boundary documentation.
How do I draw a system boundary in PlantUML?
Place related use cases inside a rectangle block named after the system. Keep external actors outside the block and connect them to the goals they use.
What is the difference between include and extend?
Include represents behavior that is always reused by another use case. Extend represents optional or conditional behavior added to a base use case.
Can I export the use case diagram as PNG or SVG?
Yes. Preview the diagram, then download PNG for slides and quick sharing or SVG for scalable documentation and web use.
Do I need to install PlantUML, Java, or Graphviz?
No. The online tool uses a server-backed preview, so you can edit and render the diagram directly in the browser.
Need AI-Assisted Diagram Editing?
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