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Sankey diagram (v10.3.0+) ​

A sankey diagram is a visualization used to depict a flow from one set of values to another.

WARNING

This is an experimental diagram. Its syntax are very close to plain CSV, but it is to be extended in the nearest future.

The things being connected are called nodes and the connections are called links.

Example ​

This example taken from observable. It may be rendered a little bit differently, though, in terms of size and colors.

Code:
mermaid

Syntax ​

The idea behind syntax is that a user types sankey-beta keyword first, then pastes raw CSV below and get the result.

It implements CSV standard as described here with subtle differences:

  • CSV must contain 3 columns only
  • It is allowed to have empty lines without comma separators for visual purposes

Basic ​

It is implied that 3 columns inside CSV should represent source, target and value accordingly:

Code:
mermaid

Empty Lines ​

CSV does not support empty lines without comma delimiters by default. But you can add them if needed:

Code:
mermaid

Commas ​

If you need to have a comma, wrap it in double quotes:

Code:
mermaid

Double Quotes ​

If you need to have double quote, put a pair of them inside quoted string:

Code:
mermaid

Configuration ​

You can customize link colors, node alignments and diagram dimensions.

html
<script>
  const config = {
    startOnLoad: true,
    securityLevel: 'loose',
    sankey: {
      width: 800,
      height: 400,
      linkColor: 'source',
      nodeAlignment: 'left',
    },
  };
  mermaid.initialize(config);
</script>

You can adjust links' color by setting linkColor to one of those:

  • source - link will be of a source node color
  • target - link will be of a target node color
  • gradient - link color will be smoothly transient between source and target node colors
  • hex code of color, like #a1a1a1

Node Alignment ​

Graph layout can be changed by setting nodeAlignment to:

  • justify
  • center
  • left
  • right