Sankey diagram maker
Paste your flows as “Source, Target, Value” lines and get a layered Sankey diagram with value-proportional ribbons — great for budgets, energy, traffic or any flow. Laid out and drawn as inline SVG in your browser, ready to export as SVG or PNG.
Open Sankey diagram maker →What is the Sankey diagram maker?
A free, private Sankey diagram maker that turns plain flow lines into a layered diagram with value-proportional ribbons, ideal for budgets, energy, web traffic or any flow of quantities. You paste your flows as "Source, Target, Value" lines and the diagram is laid out and drawn as inline SVG entirely in your browser, so nothing is uploaded and it keeps working offline.
How to use Sankey diagram maker
- Enter your flows — Type or paste one flow per line as Source, Target, Value — for example "Budget, Housing, 1900". A sample budget is loaded to start from.
- Watch it draw — The diagram regenerates as you type, sizing each ribbon and node in proportion to its value across the layers it spans.
- Add a title and tidy up — Give the chart a title, and toggle "show values" to print each node's total next to its label. The hint line tells you how many flows were read and flags any skipped lines.
- Export — Download the finished diagram as a crisp SVG that scales to any size, or as a PNG for slides and documents.
Frequently asked questions
What format does the input use?
Each flow is one line: Source, Target, Value. You can separate the three parts with commas, semicolons, tabs or arrows (-> or =>), and the value is always the last number on the line.
Is my data uploaded anywhere?
No. Your flows are parsed and the diagram is laid out and drawn in your browser, so nothing leaves your device and the tool keeps working offline.
Why was a line skipped?
A line is ignored if it has fewer than three parts, has a value that is zero or negative, or points a node back at itself. The hint under the diagram lists the line numbers it skipped so you can fix them.
Can I export it for printing?
Yes. Export to SVG for a vector that stays sharp at any size, which is best for print, or to PNG for a fixed-resolution image to drop into a document or slide deck.
Tips
- Start lines with # to add comments that the parser ignores.
- Turn on "show values" before exporting so each node's total is visible in the saved image.
- Choose SVG when you plan to print or resize the diagram so the ribbons stay sharp.