Flowchart

Use Mermaid flowchart for process logic, branching, pipelines, decision trees, and system flows.

Basic template

flowchart TD
    A[Start] --> B{Decision}
    B -->|Yes| C[Do work]
    B -->|No| D[Stop]

Core syntax

• Start with flowchart TD, LR, BT, or RL
• Common node shapes:
  • A[Step] rectangle
  • B(End) rounded
  • C{Decision} diamond
  • D[(Database)] cylinder
• Connect with -->
• Label an edge with -->|label|
• Group related nodes with subgraph

Common example

flowchart LR
    subgraph Intake
        A[Receive file] --> B[Validate columns]
    end

    B -->|Valid| C[Transform data]
    B -->|Invalid| E[Reject and notify]
    C --> D[(Warehouse)]
    D --> F[Build report]

Good for

• Business processes
• ETL pipelines
• Troubleshooting paths

Watch for

• Flowcharts get noisy when you try to model too much timing or state
• If order over time matters, sequence or gantt may be a better fit