PlantUML to Mermaid Converter
Seamlessly convert PlantUML diagrams into Markdown-native Mermaid syntax. 100% in-browser processing with real-time SVG rendering and intelligent fallback.
Paste your PlantUML architecture. The client engine normalizes calls, notes, databases, and control branches.
Review the rendered SVG output in real-time to ensure arrow logic, labels, and roles match your requirements.
Directly copy to GitHub or Notion. For edge-case C4 diagrams, use our AI Prompt Bridge for instant LLM synthesis.
PlantUML vs. Mermaid Syntax Cheat Sheet
A quick-reference comparison between PlantUML formatting and Mermaid.js markdown:
| Element Type | PlantUML Source | Mermaid Syntax |
|---|---|---|
| Declaration | @startuml ... @enduml |
sequenceDiagram / classDiagram |
| Database / Storage | database "User DB" as DB |
participant DB as User DB |
| Synchronous Request | Client -> Server: Request |
Client->>Server: Request |
| Dotted Response | Server --> Client: 200 OK |
Server-->>Client: 200 OK |
| Conditional Branch | alt successful ... else ... end |
alt successful ... else ... end |
| Loop Execution | loop 5 times ... end |
loop 5 times ... end |
Frequently Asked Questions
Why switch from PlantUML to Mermaid in 2026?
Mermaid is supported natively by GitHub, GitLab, Notion, Azure DevOps, and Obsidian without running Java runtimes or external Graphviz servers.
What happens if my PlantUML contains complex skinparam configs?
Our robust parsing engine automatically converts non-diagram styling parameters into clean Mermaid comments (%%) to ensure the core visual diagram never crashes.