Proportional Flow Widths
Link widths automatically scale to reflect flow values, making dominant paths immediately visible without any manual adjustment.
Chart & Visualization Tools
Flow Diagram Maker
Create professional Sankey diagrams that show exactly how resources, energy, or data move through your system. Proportional flow widths make the story unmistakable at a glance.
Features
Everything You Need in a Flow Diagram Maker
Purpose-built controls for Sankey diagrams — not generic chart settings.
Custom Node Colors
Assign distinct colors to each node or use gradient flows to trace paths visually from source to destination.
AI-Powered Generation
Describe your flow in plain language and the AI builds a complete Sankey diagram with nodes, links, and values ready to refine.
Flexible Node Editor
Add, remove, rename, and recolor nodes on the fly — the diagram updates live so you always see the full picture.
Label and Value Control
Toggle node labels and flow values on or off, and adjust font sizes to keep diagrams clean at any complexity level.
Instant Export
Download your flow diagram as a high-quality PNG or SVG in one click — no watermarks, no waiting.
Data input
Bring Your Flow Data In Any Format
Type It Directly
Define nodes and link values manually using the simple flow editor — no spreadsheet needed.
Paste From Spreadsheet
Copy source-target-value rows from Excel or Google Sheets and paste them straight into the tool.
Upload CSV or Excel
Import structured flow data files directly for instant Sankey diagram generation (Pro).
Describe It to AI
Tell the AI what flows you want to visualize and get a ready-made Sankey diagram in seconds.
Share
Share Your Sankey Diagram Anywhere
Download as PNG or SVG
Export crisp, high-resolution images ready for reports, slides, and publications.
Share via Link
Generate a shareable URL so teammates or clients can view your flow diagram instantly.
Embed on Your Site
Add a live Sankey diagram to any webpage with a single embed code snippet (Plus and above).
Add to Presentations
Drop the downloaded image straight into PowerPoint, Google Slides, or Keynote.
About This Flow Diagram Maker
MakeCharts built this Sankey flow diagram tool so anyone can turn complex flow data into a clear visual in minutes. No coding. No design tools. No manual calculations. Just your data and a finished diagram ready to share.
<2 minTime to First Diagram
50+Chart Styles Available
12+Languages Supported
10k+Diagrams Created
ZeroDesign Skills Required
Workflow
Build a Flow Diagram in 3 Steps
Define Your Nodes
Add the categories or stages in your flow — sources, processes, and outputs. Name each node to match your data story.
Connect Flows With Values
Link nodes with directional flows and assign a numeric value to each. The diagram automatically sizes link widths proportionally.
Customize and Export
Adjust colors, labels, spacing, and animation speed. Then download your Sankey flow diagram or share it via link.
Use cases
Where Sankey Flow Diagrams Excel
Energy Flow and Loss Analysis
Map how input energy converts and dissipates across a system to pinpoint inefficiencies. Sankey diagrams are the industry standard for energy audits and sustainability reporting.
Budget and Revenue Flow Visualization
Show how money moves through an organization — from top-line revenue down to net profit — so stakeholders grasp the full financial picture instantly.
User Journey and Traffic Funnels
Visualize where users enter, navigate, and drop off across your product or website to identify conversion bottlenecks at a glance.
Material and Resource Flows
Track raw materials through manufacturing stages to finished goods, making supply chain complexity understandable for any audience.
Templates
Start with professionally designed templates
Carbon Circular Flow Sankey: See Where Carbon Goessankey
Visualize your carbon circular flow instantly. Spot emissions, recycling, and sequestration hotspots to improve ESG reporting and cut footprint fast.
Sankey Diagram Template - Map Flows ClearlysankeyStart with a blank Sankey template to map energy, budget, or process flows. Customize nodes, links, and colors instantly - no design skills needed.
Energy Flow Sankey Diagram TemplatesankeyVisualize energy sources, generation, and consumption with this free Sankey diagram template. Track flows from coal, gas, and renewables to end sectors.
Water Flow Sankey Diagram TemplatesankeyMap the full water cycle — from rainfall and snowmelt to treatment plants, residential use, and beyond — with this free Sankey diagram template.
Supply Chain Sankey Diagram TemplatesankeyVisualize your supply chain flows from raw materials to end consumers with this free Sankey diagram template. Track product movement and returns.
Blank Sankey Diagram TemplatesankeyStart with a blank Sankey diagram template to visualize revenue flows, budgets, and processes. Free, customizable, and AI-powered. No account needed.
Related Tools
Create similar charts with these tools
Sankey Diagram Makersankey
Create stunning Sankey diagrams in minutes. Visualize flows, energy transfers, and resource allocation with our free AI-powered Sankey diagram generator.
Sankey Diagrams Without ExcelsankeySkip the Excel workarounds. Build a Sankey diagram in seconds with AI. Visualize flows, budgets, and processes — free, no sign-up needed. No plugins.
Energy Flow Diagrams, InstantlysankeyBuild stunning energy flow diagrams instantly with AI. Visualize where energy goes, spot waste, and present findings clearly. Free Sankey diagram maker.
Sankey Diagrams, Built InstantlysankeyBuild interactive Sankey diagrams in seconds. Visualize energy flows, budget allocations, and process data with our free AI-powered Sankey diagram maker.
Comparison
Flow Diagram Maker vs. Manual Diagramming
See why teams switch from traditional tools to AI-powered Sankey creation.
MakeCharts Flow Diagram Maker
- Proportional flow widths calculated and drawn automatically
- Describe your flow in plain language and get a diagram instantly
- Edit any value and the diagram updates live
- AI generates a complete Sankey from a single sentence
- Intuitive node and link editor — no design skills needed
- Free PNG and SVG export with no watermarks
Manual Tools (Visio, Draw.io)
- Hours spent sizing and aligning flow links by hand
- Values and widths must be calculated and drawn manually
- Updating data means rebuilding the whole diagram
- No AI to suggest structure or generate from a description
- Steep learning curve for non-designers
- Export formats limited or behind paywalls
FAQ
Frequently Asked Questions
What is a flow diagram maker?
A flow diagram maker is an online tool that helps you create visual diagrams showing how quantities move between categories or stages. Our flow diagram maker specializes in Sankey charts, where link widths represent the magnitude of each flow — making proportions immediately visible.
What is a Sankey diagram and when should I use one?
A Sankey diagram is a type of flow chart where the width of each arrow or link is proportional to the flow quantity it represents. Use it whenever you need to show how a total quantity — energy, money, traffic, or material — splits and recombines across a system. It is especially powerful for revealing where the largest losses or transfers occur.
Is this flow chart maker really free?
Yes. You can create, customize, and download Sankey flow diagrams at no cost with no sign-up required. Free accounts also include AI credits so you can try AI-powered diagram generation. Paid plans unlock more AI usage, file uploads, and embed codes.
Can I make a flow chart with multiple levels?
Absolutely. Our Sankey diagram tool supports multi-stage flows where the same node can receive flows from one layer and send flows to the next. This is ideal for complex systems like supply chains, budget waterfalls, or multi-step user journeys.
How do I create a Sankey diagram from my data?
Add your nodes (categories) using the node editor, then define links by selecting a source node, a target node, and a flow value. The diagram renders instantly. You can also paste data from a spreadsheet or use the AI to generate a starting diagram from a plain-language description.
Can I use the AI flow diagram maker to generate charts automatically?
Yes. Just type a description of your flow into the prompt box — for example, 'Show how a $1M marketing budget is split across channels and then converts to leads and sales' — and the AI will generate a complete Sankey chart with nodes, links, and values ready for you to refine.
What file formats can I export my Sankey diagram in?
You can download your flow diagram as a high-resolution PNG for presentations and documents, or as an SVG for scalable, print-quality output. Both formats are watermark-free on all plans.
How is a Sankey diagram different from a regular flow chart?
A regular flow chart shows steps and decisions using boxes and arrows of uniform size. A Sankey diagram encodes quantity in the width of each link, so you can see not just the direction of flow but also the relative magnitude of each path. This makes Sankey diagrams far more powerful for quantitative flow analysis.
Built for Everyone Who Works With Flows
- No design background needed — the tool handles proportions and layout automatically
- Works equally well for simple 3-node flows and complex multi-stage systems
- Available in 12+ languages so your whole team can use it
- Fully functional on desktop, tablet, and mobile
- Free tier has no feature gating — all chart controls are accessible without a subscription
- AI generation lowers the barrier for users unfamiliar with Sankey diagram conventions
Your Flow Data Stays Yours
- Your diagram data is used only to render your chart — it is not shared with third parties
- You control what you download, share, or publish
- No data is sold or used for advertising
- You can delete your account and associated data at any time
- Shared links only expose what you explicitly choose to share
Start now
Ready to Map Your First Flow?
Create a polished Sankey flow diagram in under two minutes — free, no sign-up needed.
- Free forever plan — no credit card
- AI-powered generation included
- PNG and SVG export
- No design skills required
- Works on any device
Free to use. No account required. AI credits included.