Sequence Diagram Generator

Create sequence diagrams online with our free and simple tool. Generate SVG diagrams from text input using simple syntax, then download or copy for use in your documentation or presentations.
Sequence Diagram Generator
Syntax Guide
Basic Syntax
title Sequence Diagram Example

# Simple message exchange
Peter->Taylor: Hello Taylor, how are you?
Taylor->Peter: I'm doing great, thank you!

# Asynchronous message
Peter-->Taylor: Here's a document to review
note over Taylor: Reading document...

# Response after delay
Taylor->Peter: The document looks good
note over Peter,Taylor: Document approved

# Emphasized message
Peter=>Taylor: Let's finalize the project!
Arrow Types
  • ->: Synchronous message
  • -->: Asynchronous message (dotted line)
  • =>: Thick arrow (emphasized message)
  • <-, <--, <=: Reply messages (reverse direction)
Notes
  • note over [Participant]: Note above a participant
  • note over [Participant1],[Participant2]: Note spanning multiple participants
  • note left of [Participant]: Note to the left of a participant
  • note right of [Participant]: Note to the right of a participant
Text Formatting
  • **bold text**: Bold text
  • __italic text__: Italic text
  • \n: Line break
Tips
  • Use comments starting with # to organize your diagram
  • Add a title with 'title Your Diagram Title'
  • You don't need to declare participants explicitly, they are automatically detected from messages
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