How to Create a Bubble Chart in Power BI

Bubble charts are an excellent way to show the relationship between three different sets of data in one spot. Unlike a standard scatter plot that handles two variables, a bubble chart adds a third dimension by changing the size of the data points, or "bubbles." This article will walk you through exactly how to create, customize, and get the most out of a bubble chart in Power BI.

What Exactly is a Bubble Chart?

Think of a bubble chart as a smarter, more informative cousin of the scatter plot. While a scatter plot uses an X-axis and a Y-axis to plot data points, a bubble chart does the same and then adds a third numeric measure to control the size of each bubble. This lets you quickly spot relationships and patterns that would be difficult to see otherwise.

For example, you could plot your products on a chart where:

• The X-axis shows the number of units sold.
• The Y-axis shows the profit margin for each sale.
• The size of the bubble represents the total revenue generated.

Instantly, you can identify products that sell a lot and have high margins (big bubbles in the top right), products that are popular but have low margins (big bubbles in the bottom right), or niche products with great margins but low volume (small bubbles in the top left). You’re telling a multi-layered story with a single visual.

When Is a Bubble Chart the Right Choice?

Bubble charts are most effective when you're trying to compare items based on three quantitative values. They excel at showcasing relationships and outliers in your data. Here are a few ideal scenarios:

• Analyzing Marketing Campaigns: Compare campaigns by plotting marketing spend (X-axis), customer lifetime value (CLV) (Y-axis), and the number of conversions (bubble size). This can reveal which campaigns are both cost-effective and bring in high-value customers.
• Evaluating Sales Performance: Assess sales reps by charting the number of deals closed (X-axis), the average deal size (Y-axis), and the total revenue generated (bubble size).
• Understanding Web Traffic: Plot pages on your website with time on page (X-axis), bounce rate (Y-axis), and total pageviews (bubble size). This helps identify popular pages that might need content improvements to reduce bounce rates.
• Portfolio Analysis: In finance, you can compare different investments by risk (X-axis), reward/return (Y-axis), and the amount invested (bubble size).

A good rule of thumb: if you find yourself creating multiple bar charts or scatter plots to compare the same items across three different metrics, a bubble chart can likely combine that information into a single, more intuitive visual.

Getting Your Data Ready for Power BI

Before jumping into Power BI, having your data structured correctly will make the process much smoother. For a bubble chart, your dataset needs at a minimum:

• Three numeric columns: One for the X-axis, one for the Y-axis, and one to determine the bubble size.
• One categorical column (optional but recommended): This column will be used to label and color-code the bubbles, such as "Product Name," "Campaign Name," or "Country."

Let’s use an example of marketing campaign data. Here’s how a simple table in Excel or a Google Sheet might look:

In this dataset, we have:

• X-axis candidate: Clicks (numeric)
• Y-axis candidate: Conversions (numeric)
• Size candidate: Spend (numeric)
• Category candidate: Campaign Name (text)

Ensure your number columns are formatted as numbers and your category column is formatted as text before importing into Power BI to avoid any snags.

Step-by-Step: Creating a Bubble Chart in Power BI

With your data ready, it’s time to build the chart. In Power BI, a bubble chart isn't its own distinct visual, it's an extension of the Scatter chart. Here's how to create one.

1. Load Your Data into Power BI

First, open Power BI Desktop. In the Home ribbon, click on "Get data" and select the source of your data (e.g., Excel workbook, SQL server). Navigate to your file and load it into your report.

2. Select the Scatter Chart Visual

Once your data is loaded, look at the Visualizations pane on the right side of the screen. Click on the icon for the Scatter chart. An empty visual placeholder will appear on your report canvas.

3. Assign Your Data Fields

Now comes the important part. With the empty scatter chart visual selected, look below the visualization icons to see the data fields (or "wells") for that chart. Click and drag your data fields from the Data pane into the appropriate wells:

• X-Axis: Drag your first numeric field here. Using our example, we’d drag the Clicks field.
• Y-Axis: Drag your second numeric field here. We’ll use Conversions.
• Legend: Drag your categorical field here. This will differentiate the bubbles. We’ll use Campaign Name.
• Size: This is the crucial step that turns the scatter plot into a bubble chart. Drag your third numeric field here. We are using Spend. You'll immediately see the dots on your chart change in size.

4. (Optional) Add a Play Axis for an Animated Chart

If your dataset includes a time-based field like a date or month, you can create a dynamic, animated bubble chart. Drag your date field into the Play Axis well. This adds a timeline at the bottom of your chart. When you press the play button, the bubbles will move and change size to show how your data has evolved over time—an incredibly powerful way to visualize trends.

Customizing Your Bubble Chart for Clarity and Impact

You’ve built the chart, but a little formatting can go a long way in making it easy to read and professionally polished. Select your visual, then click the paintbrush icon ("Format your visual") in the Visualizations pane.

Here are some of the most useful adjustments you can make:

General Settings

• Title: Always give your chart a descriptive title. Click on 'General' -> 'Title' and write something clear like "Campaign Performance: Spend vs. Conversions & Clicks."

Visual Settings

• Colors: Under the 'Markers' dropdown, you can change the color associated with each category in your legend. This is useful for aligning with company branding or using color psychology (e.g., green for high-performing campaigns).
• Category labels: By default, viewers have to rely on the legend to know what each bubble represents. You can make it easier by turning on Category labels. This will display the name of each category directly on or next to its bubble.
• Data labels: Under the 'Data labels' dropdown, toggle the switch to "On." This displays the actual values for the data points on your chart, making it easier for users to understand the precise data without having to hover over each bubble.
• Axis customization: Expand the 'X-Axis' and 'Y-Axis' sections to change their titles to be more descriptive, adjust the font size, and set a minimum or maximum range if needed. This can help you "zoom in" on the most important part of the data.
• Marker transparency: In the 'Markers' section, you can adjust the transparency. If you have several bubbles overlapping, increasing the transparency can help you see them all more clearly.
• Negative Values: Power BI provides an option to show negative values if your bubble size metric can be negative (e.g., Profit). You can find this under 'Markers' -> 'Negative values.'

Advanced Tip: Use Tooltips for Deeper Context

Want to provide extra information without cluttering your chart? Use the Tooltips well.

Anything you drag into this field won't be displayed on the chart directly, but it will appear in a pop-up box when a user hovers their mouse over a bubble. For our marketing campaign example, you could add metrics like "Return on Ad Spend (ROAS)" or "Cost Per Conversion" to the Tooltips field. This way, users can explore individual bubbles to get a deeper layer of insights on demand.

Final Thoughts

Bubble charts in Power BI offer a fantastic way to represent three dimensions of data in a single visualization, turning a complex dataset into an easily understood story. By leveraging the scatter chart visual and assigning a metric to the "Size" field, you can quickly uncover relationships between your data points that might otherwise go unnoticed.

Of course, building dashboards, even straightforward ones, involves pulling data from various sources, cleaning it, and configuring each visual. To accelerate this process, we built Graphed. After easily connecting your data sources like Google Analytics, Shopify, or Salesforce, you can simply ask for what you want in plain English, like "Create a dashboard comparing our recent campaigns by spend, conversions, and clicks," and instantly get a live, real-time dashboard without any manual chart-building, saving you hours of repetitive work.