Sankey diagrams are a powerful tool for visualizing and understanding complex flow data. They are particularly useful for depicting energy, material, or financial flows in a clear and intuitive manner. With the right tools, creating Sankey diagrams in Excel can be an efficient and effective process. In this blog post, we will explore how to create Sankey diagrams in Excel, step by step, and uncover the benefits they offer for data visualization.
Understanding Sankey Diagrams

A Sankey diagram is a type of flow diagram in which the width of the arrows or paths is proportional to the quantity or flow rate. It provides a visual representation of how a resource moves through a system, highlighting the most significant flows and pathways. This diagram is especially effective for visualizing energy, material, or financial flows, as it helps identify key trends, bottlenecks, and areas of interest.
The beauty of Sankey diagrams lies in their ability to convey complex information in a simple and visually appealing way. By using varying widths to represent different flow rates, these diagrams offer a quick understanding of the data without overwhelming the viewer with numbers or detailed explanations.
Benefits of Using Sankey Diagrams

There are several advantages to utilizing Sankey diagrams for data visualization:
- Clear Visualization of Flows: Sankey diagrams provide a clear and concise representation of flow data, making it easy to identify the most significant pathways and trends.
- Highlighting Important Information: By emphasizing the width of the arrows, Sankey diagrams draw attention to the most critical flows, helping viewers focus on the key aspects of the data.
- Identifying Bottlenecks and Inefficiencies: These diagrams can reveal areas where resources are being wasted or utilized inefficiently, allowing for better decision-making and process optimization.
- Communicating Complex Data Simply: With their intuitive visual representation, Sankey diagrams make it easier to communicate complex flow data to a wide range of audiences, from experts to laypeople.
Creating Sankey Diagrams in Excel

While specialized software exists for creating Sankey diagrams, Excel offers a more accessible and familiar option for many users. Here's a step-by-step guide on how to create a Sankey diagram in Excel:
Step 1: Prepare Your Data
Start by organizing your data in a structured manner. Ensure that you have the following columns in your Excel sheet:
- Source: The starting point of the flow.
- Target: The destination or endpoint of the flow.
- Value: The quantity or flow rate associated with each flow.
For example, if you are visualizing energy flows in a power plant, your data might look like this:
Source | Target | Value |
---|---|---|
Coal | Boiler | 1000 |
Boiler | Turbine | 800 |
Turbine | Generator | 750 |
Generator | Grid | 700 |

Step 2: Install the Sankey Diagram Add-in
Excel does not have a built-in feature for creating Sankey diagrams, but you can use an add-in to achieve this. One popular option is the Sankey Diagram Add-in by Think-Cell. Follow these steps to install it:
- Go to the Think-Cell website and download the add-in.
- Open Excel and go to the File tab.
- Select Options and navigate to the Add-Ins section.
- Choose COM Add-Ins from the drop-down menu and click Go.
- Browse to the location where you saved the Think-Cell add-in and select it.
- Click OK to install the add-in.
Step 3: Create the Sankey Diagram
Once the add-in is installed, follow these steps to create your Sankey diagram:
- Select the range of cells containing your data, including the headers.
- Go to the Think-Cell tab in the Excel ribbon.
- Click on the Sankey Diagram button.
- A dialog box will appear, allowing you to customize the appearance of your diagram. You can choose the layout, color scheme, and other visual settings.
- Click OK to generate your Sankey diagram.
Your Sankey diagram will be inserted into your Excel sheet, providing a visual representation of the flows in your data.
Step 4: Customize and Enhance Your Diagram
After creating your Sankey diagram, you can further customize it to meet your specific needs:
- Adjust Width and Height: Resize the diagram by dragging the sizing handles.
- Edit Data Labels: Double-click on a flow to edit the source, target, and value labels.
- Change Colors: Right-click on a flow and select Format Shape to change the color or apply different effects.
- Add Annotations: Use the text box tool to add additional notes or explanations to your diagram.
Tips and Best Practices

When creating Sankey diagrams in Excel, keep these tips in mind to ensure effective visualization:
- Use Clear and Concise Labels: Ensure that your source, target, and value labels are easy to understand and free from jargon.
- Consider Color Blindness: Choose color schemes that are accessible to all viewers, avoiding color combinations that may be difficult for color-blind individuals to distinguish.
- Keep It Simple: Focus on the most important flows and avoid cluttering your diagram with unnecessary details.
- Provide Context: Include a brief explanation or caption to help viewers understand the purpose and key insights of your diagram.
Conclusion

Sankey diagrams offer a powerful way to visualize flow data, making complex information more accessible and understandable. By following the steps outlined in this blog post, you can create Sankey diagrams in Excel, a familiar and widely available tool. Whether you are visualizing energy flows, material movements, or financial transactions, Sankey diagrams can help you identify trends, bottlenecks, and areas for improvement. With their intuitive visual representation, these diagrams can effectively communicate complex data to a wide range of audiences, making them a valuable addition to your data visualization toolkit.
FAQ

What is a Sankey diagram used for?
+Sankey diagrams are primarily used to visualize flow data, such as energy, material, or financial flows. They help identify trends, bottlenecks, and key pathways in a system.
Can I create a Sankey diagram without specialized software?
+Yes, you can create Sankey diagrams in Excel by using add-ins like the Think-Cell Sankey Diagram Add-in. This provides a more accessible option for those familiar with Excel.
How do I customize the appearance of my Sankey diagram in Excel?
+After creating your diagram, you can adjust its size, edit data labels, change colors, and add annotations to enhance its visual appeal and clarity.