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MERMAID DIAGRAM GUIDE

Mermaid ZenUML diagram online editor

Write concise sequence diagrams for object interactions and messages. Create the diagram in Mermaid Studio, preview it instantly, and export it when it is ready to share.

Open the ZenUML editor See an example

WHAT IT IS FOR

Make the important relationships clear

Write concise object interactions when a compact sequence notation makes a service or application flow easier to review.

Document object interactions
Explain nested service calls
Sketch a concise API flow

Why use Mermaid Studio?

Write the source as versionable Mermaid code.
Preview changes immediately in the browser.
Export the finished diagram as SVG or PNG.
Start from a related template when you need a head start.

MERMAID EXAMPLE

Start with a working example

Copy the structure, replace the labels with your own domain, and continue in the full editor.

zenuml
  title Payment Approve Flow
  User->App: Start payment
  App->Payment.authorize() {
    Payment->Bank: Approve Request
    Bank->Payment: Approve Result
  }
  Payment->App: Payment complete

HOW TO START

Create your diagram in four steps

1Name the objects involved in the interaction.
2Write messages in execution order.
3Use blocks for nested calls or grouped work.
4Review the diagram with the implementation owner.

WRITING TIPS

Keep the diagram useful

Keep each message focused on one interaction.

Use clear object names throughout the diagram.

FAQ

Frequently asked questions

What is ZenUML?+

ZenUML is a concise syntax for describing sequence-style interactions between objects and services.

When should I choose ZenUML over sequence syntax?+

Choose it when nested calls and compact object-oriented notation make the interaction easier to communicate.

TEMPLATES

Start from a related template

Payment interaction sequence

Describe the objects and messages involved in a payment flow.

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Organize ideas and subtopics hierarchically around a central theme.

Ready to make a ZenUML?

Open the editor with a working example and adapt it to your project.

Start in Mermaid Studio