Free ZenUML Sequence Diagram Maker Online

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Free ZenUML Sequence Diagram Maker Online

Write sequence diagrams with intuitive, code-like ZenUML syntax for clearer system interactions.

What is a ZenUML Diagram?

ZenUML is an alternative syntax for creating sequence diagrams that uses a code-like, developer-friendly format. Instead of arrow-based notation, ZenUML uses method calls and curly braces to represent interactions, making it more natural for programmers. It supports the same concepts as traditional sequence diagrams but with a syntax that feels like writing code.

Common Use Cases

  • API documentation - Document service interactions with code-like syntax
  • Developer communication - Express sequence logic in familiar programming style
  • Microservice interactions - Show service-to-service method calls
  • Code review - Visualize complex call chains before implementation
  • Technical specifications - Define interaction contracts between services

Syntax Quick Reference

ElementSyntaxDescription
Titletitle NameDiagram heading
Participant@Actor NameDefine an actor or participant
Method callA->B.method(args)Synchronous call
Nested call{ ... }Calls within a method scope
Returnreturn valueReturn from a method call
Stereotype@Boundary, @EntityParticipant type annotation

Export Options

PNG Export

High-resolution images for documents and presentations.

SVG Export

Scalable vectors for web and further editing.

PDF Export

Print-ready format for professional documentation.

Frequently Asked Questions

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