Alluvial Diagram Chart
Free Online Alluvial Diagram Chart Maker
What is an Alluvial Diagram Chart?
An alluvial diagram chart visualizes how quantities flow and redistribute across multiple stages or time points, showing which categories gain or lose share at each step. It maps categorical data as blocks (nodes) connected by curved streams whose width is proportional to the flow value. Use it when you need to reveal how a population, budget, or dataset shifts composition as it passes through successive categories — making patterns of change that are invisible in a table instantly clear.
Key Features
Multi-Stage Flow Mapping
Add as many stages (columns) as your data needs and define categories within each stage to trace exactly how values move from one classification to the next.
Proportional Stream Widths
Each connecting stream is drawn at a width proportional to its flow value, so the visual weight of a path directly reflects its real-world magnitude.
Flexible Color Modes
Color flows by source category, target category, or a gradient blend — making it easy to follow a single group across all stages or highlight where paths converge.
Adjustable Node Layout
Control node width, spacing between categories, and flow curvature so the diagram stays readable whether you have 3 categories or 30.
Inline Value Labels
Toggle flow values and category labels on or off, with configurable font sizes, so your chart communicates clearly in both presentations and reports.
AI-Powered Data Entry
Describe your stages and flows in plain text and the AI alluvial diagram chart generator builds the diagram instantly — no manual node-and-link setup required.
Best For
When to Use
- Your data has two or more ordered stages and you want to show how totals redistribute between them
- You need to trace specific categories — not just totals — through each transition
- The share of each category changes meaningfully between stages and that change is the story
- A simple stacked bar chart hides which segments are converting, growing, or churning
- You are presenting a process flow where the 'how much goes where' question matters as much as the sequence itself
- You have at least three categories per stage — otherwise a simple Sankey or flow chart is sufficient
Common Mistakes
- !Adding too many categories per stage, which creates a tangle of thin streams that are impossible to follow
- !Using flow values that do not balance across stages, implying data appears or disappears without explanation
- !Choosing colors that are too similar across adjacent categories, making streams visually indistinguishable
- !Labeling every single flow with its value when the diagram already has many streams — prefer labels only on significant flows
- !Mixing up the direction of flows by defining source and target in inconsistent order across rows
- !Using an alluvial diagram for continuous numeric data — it is designed for categorical transitions, not time-series trends