Behavioral UML
Communication Diagram Maker
Use a communication diagram when structural links matter as much as message order. Start from the template, number messages clearly, and export for design notes.
Features
- Live editor for communication diagram maker
- 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
Communication diagrams show collaborating objects and numbered messages along their links. They help when layout of who talks to whom matters as much as call order.
How to use this maker
Place collaborating objects, number messages in call order, preview the graph, then export PNG or SVG for design notes.
Notation that matters
Objects sit as nodes. Links show structural relationships. Message numbers carry the sequence. Keep numbering dense and continuous so readers can follow the story without a time axis.
Keep the diagram readable
Sequence diagrams emphasize time and activations. Prefer those when timing matters. Use an object diagram for a value snapshot without messages, and a class diagram for type structure.
Frequently asked questions
Is this communication diagram maker free?
Yes. Create and export online without a paid plan.
Can this replace a sequence diagram?
Sometimes for small collaborations. Prefer sequence diagrams when timing and activations matter.
Communication diagram or object diagram?
Object diagrams show instance values. Communication diagrams add numbered messages on top of collaboration links.
Related tools
- Sequence Diagram MakerDraw a sequence diagram for auth flows, service calls, and feature interactions. Start from the temp…
- Object Diagram MakerDraw an object diagram when you need a snapshot of instances, not just types. Start from the templat…
- Class Diagram MakerBuild a UML class diagram in your browser. Start from the template, rename types to match your domai…
Browse the full UML diagram tools directory or return to the UML diagram hub.