Shows flow quantities between nodes as weighted links, useful for energy or resource flows. The width of each link is proportional to the flow quantity, making it easy to see the largest flows and trace paths through the system.
Follow the Money — NASA's $25.4B Budget Flow
Best for
- Visualizing energy, material, or resource flows through a system
- Showing how quantities split and merge across stages
- Tracing the path of values from source to destination
Avoid when
- The flow is circular — Sankey diagrams are for directional flows
- You have too many nodes — the diagram becomes cluttered
- You need to show time-series changes in flows