Sankey Diagram Maker
Visualize flows, transfers, and allocations in seconds.
Turn complex flow data into clear, proportional Sankey diagrams. Map energy, money, traffic, or any multi-stage process without writing a single line of code.
Everything You Need to Build Sankey Diagrams
Purpose-built controls for flow visualization — no generic chart clutter.
Proportional Flow Widths
Link widths automatically scale to reflect flow values, so viewers grasp magnitude at a glance. No manual sizing needed.
Custom Node Colors
Assign distinct colors to each node category to make multi-source flows instantly distinguishable.
AI-Powered Generation
Describe your process in plain language and the AI builds a ready-to-use Sankey diagram, including nodes and weighted links.
Flexible Layout Controls
Adjust node width, spacing, link opacity, and label font size to match your exact presentation needs.
Gradient or Node Coloring
Choose between node-based colors for category clarity or gradient flows for a polished, modern look.
Instant Live Preview
Every edit updates the diagram in real time so you can iterate quickly and see results before exporting.
Add Your Flow Data Your Way
Type It In
Define nodes and link values directly in the editor with a simple, guided interface.
Paste from Spreadsheet
Copy your source-target-value table from Excel or Google Sheets and paste it instantly.
Describe with AI
Tell the AI what flows to visualize and it builds the Sankey diagram for you automatically.
Upload a File
Import CSV or Excel files directly for large or complex multi-node flow datasets (Pro).
Share Your Sankey Diagram Anywhere
Download as PNG or SVG
Export crisp, high-resolution images ready for reports, slides, and publications.
Share a Link
Get a shareable URL and send your Sankey diagram to collaborators or clients instantly.
Embed on Your Site
Drop a lightweight embed code into any website or blog post to display your diagram live.
Use in Presentations
Paste directly into PowerPoint, Google Slides, or Notion for polished, data-driven decks.
About MakeCharts Sankey Diagram Maker
MakeCharts is a free online chart maker built for speed and clarity. The Sankey diagram tool is designed specifically for flow visualization — with proportional links, custom node colors, and AI generation built in. From energy analysts to product managers, thousands of users create Sankey diagrams here every month.
- ✓Dedicated Sankey diagram editor with node and link controls
- ✓AI generation from plain-language descriptions
- ✓Real-time live preview as you edit
- ✓Export to PNG, SVG, or embed code
- ✓Part of a 50+ chart type platform — all free to start
- ✓No installation, no account required for basic use
By the Numbers
How to Make a Sankey Diagram
From raw flow data to a finished diagram in three steps.
Define Your Nodes
Add the categories or stages in your flow — sources, processes, and outputs. Give each a name and an optional color.
e.g. 'Coal', 'Natural Gas', 'Electricity Generation', 'Heat Loss', 'End Use'
Set Your Flow Links
Connect nodes with directional links and assign a numeric value to each. The width of each link will reflect that value proportionally.
e.g. Coal → Electricity Generation: 450 | Electricity Generation → Heat Loss: 180
Customize and Export
Adjust colors, labels, spacing, and opacity. Download your Sankey diagram as PNG or SVG, or grab the embed code.
e.g. Switch to gradient flows, increase node spacing, and download as SVG for a report
Who Uses Sankey Diagrams
Any time quantities flow from one stage to another, a Sankey diagram tells the story.
Energy Flow Analysis
Show how energy moves from primary sources through conversion losses to end uses. Sankey diagrams are the standard format for energy audits and sustainability reports.
Budget and Revenue Allocation
Visualize how revenue is distributed across costs, departments, and profit centers. Make budget decisions transparent for stakeholders.
User Journey and Funnel Flows
Map how users move through onboarding, feature adoption, or conversion funnels to identify drop-off points and optimization opportunities.
Material and Process Flows
Illustrate how materials, nutrients, or data transform across complex multi-stage processes in research papers and classroom presentations.
Templates
Start with professionally designed templates
AI Sankey Diagram Maker vs. Manual Tools
See why teams switch from spreadsheets and specialized software to MakeCharts.
Manual / Spreadsheet Tools
- ✗Hours spent formatting and manually sizing flow widths
- ✗Steep learning curve for specialized Sankey software
- ✗No live preview — export-to-check cycle wastes time
- ✗Hard to update when flow values change
- ✗Exporting for presentations requires extra steps
- ✗Requires paid software licenses for advanced features
MakeCharts Sankey Diagram Generator
- ✓Describe your flows and get a diagram in under 2 minutes
- ✓Guided node and link editor — no learning curve
- ✓Live preview updates instantly with every edit
- ✓Change a value and the flow widths recalculate automatically
- ✓One-click download as PNG or SVG, ready for any format
- ✓Free tier covers most use cases with no sign-up required
Frequently Asked Questions
What is a Sankey diagram?
A Sankey diagram is a flow visualization where the width of each arrow or link is proportional to the quantity it represents. They are ideal for showing how energy, money, materials, or users move through a multi-stage system. The format makes it easy to spot where the most flow goes and where losses or drop-offs occur.
How do I make a Sankey diagram with this tool?
Add your nodes (the categories or stages) in the node editor, then define links between them with a numeric flow value. The diagram builds in real time as you type. You can also use the AI generator — just describe your flow in plain language and it creates the diagram automatically.
Is this Sankey diagram maker free?
Yes. The core Sankey diagram maker is completely free to use with no sign-up required. You can create, customize, and download diagrams at no cost. Paid plans unlock more AI credits, file uploads, and embed codes.
Can I use the AI to generate a Sankey diagram?
Yes. Every account includes free AI credits. Type a description like 'show energy losses from coal to end use' and the AI will generate nodes and weighted flow links for you. You can then edit any detail manually.
What file formats can I export my Sankey diagram in?
You can download your Sankey diagram as a PNG (great for presentations and social media) or as an SVG (vector format, ideal for reports and print). Embed codes for websites are available on paid plans.
Built for Everyone
- ✓No design background needed — the tool guides you from data to finished diagram
- ✓Works in 12+ languages so global teams can collaborate naturally
- ✓Fully responsive on desktop, tablet, and mobile
- ✓Free tier with no sign-up so anyone can start immediately
- ✓Simple controls for beginners, with advanced layout options for experts
Your Data, Your Control
- •Your chart data is used only to render your diagram
- •We do not sell or share your data with third parties
- •You choose what to publish — nothing is shared without your action
- •Download or delete your account and data at any time
- •No tracking of diagram content for advertising purposes
Ready to Visualize Your Flows?
Create your first Sankey diagram in under two minutes — free, no sign-up needed.