How to Use Radar Chart in Power BI

A radar chart is one of the most effective ways to show how different items stack up against each other across several key metrics. Sometimes called a spider chart or web chart, this visualization can instantly reveal which product excels in certain features, which employee demonstrates specific skills, or which marketing campaign is overperforming on particular channels. This article will guide you through exactly what a radar chart is, and provide a step-by-step tutorial on how to build and customize one in Power BI.

What Is a Radar Chart (and When Should You Use One)?

Imagine a spider's web. A radar chart starts from a central point and has multiple axes, or "spokes," radiating outward. Each spoke represents a different quantitative variable or metric. A line is then drawn connecting the data points on each spoke, creating a polygon shape. Looking at the size and shape of these polygons allows for quick, high-level comparisons between a few different categories.

The bigger and more symmetrical the shape, the better a category is performing across all measured attributes. An asymmetrical or skewed shape instantly highlights strengths and weaknesses.

Ideal Use Cases for Radar Charts

Deciding when to use a radar chart is just as important as knowing how to create one. They shine when you need to make multivariate comparisons. Here are a few common scenarios where a radar chart is the perfect choice:

• Product Comparison: Evaluating two or three competing products across a set of features like price, usability, customer support, durability, and design.
• Employee Performance Review: Assessing team members on core competencies such as communication, teamwork, technical skill, problem-solving, and leadership.
• Campaign Performance Analysis: Comparing the effectiveness of different marketing campaigns across metrics like Reach, Engagement Rate, Click-Through Rate (CTR), and Return on Ad Spend (ROAS).
• Store or Regional Performance: Analyzing the performance of different store locations based on metrics like Sales Volume, Customer Satisfaction, Staff Count, and Operational Costs.

When to Avoid Radar Charts

Despite their strengths, radar charts aren't a one-size-fits-all solution. Using one in the wrong context can lead to confusion and misinterpretation. Here are some situations where you should choose a different type of visualization:

• Too Many Categories: Trying to plot more than three or four categories (the items being compared) will result in a visual mess of overlapping lines that's impossible to read. If you're comparing five or more items, a simple bar chart is usually more effective.
• Too Many Axes: Similarly, using more than eight to ten axes (metrics) can make the chart cluttered and hard to follow. The resulting polygon will have too many sides to interpret easily.
• Data Over Time: Radar charts are not useful for showing trends over time. For time-series data, a line chart is the standard and most effective choice.
• Very Different Scales: If your metrics have drastically different scales (e.g., comparing "Revenue" in millions of dollars to "Customer Satisfaction" on a scale of 1-5), the chart will be skewed and misleading. You'll need to standardize your data first (more on this later).

Preparing Your Data for a Power BI Radar Chart

Before you jump into Power BI, getting your data into the right shape is essential. A radar chart requires a specific data structure to function correctly. You need one column that defines the distinct categories you want to compare and several numerical columns that represent the spokes of your chart.

Your data should be "unpivoted," meaning each metric or attribute has its own dedicated column. Here is an example of a simple dataset formatted for a radar chart comparing three different software products:

Here, "Product" is our main category. "Usability," "Features," "Support," and "Price Index" are the quantitative variables that will become the axes of our radar chart.

Step-by-Step: How to Create a Radar Chart in Power BI

Now that you understand the purpose of a radar chart and how your data should be structured, let's build one in Power BI. Since the radar chart is not a native visual, you'll need to add it from Microsoft's AppSource marketplace first.

Step 1: Get the Radar Chart Visual from AppSource

Adding custom visuals to your Power BI report is straightforward.

1. In your Power BI report, look at the Visualizations pane on the right side.
2. Click the three dots (...) at the bottom of the icons.
3. From the menu that appears, select Get more visuals.
4. This will open the Power BI Visuals marketplace. Use the search bar to type "Radar Chart."
5. Several options will appear. The official one published by Microsoft Corporation is a reliable choice. Click Add to import it into your report. The icon for the radar chart will now appear in your Visualizations pane.

Once you've done this once in a report, that visual will be available for you to use anytime within that .pbix file.

Step 2: Add the Visual to Your Report and Populate the Fields

With the visual now available in your toolbox, you can add it to your report canvas and start feeding it data.

1. Click the new Radar Chart icon in the Visualizations pane to add an empty visual to your report page.
2. With the empty chart selected, look at the Fields wells below the visualization icons. You will see two primary options: Category and Y Axis.
3. Drag the column containing your main categories into the Category field. Using our example above, you would drag the "Product" column here.
4. Next, drag all of your numerical metric columns into the Y Axis field. These will become the spokes of your chart. Drag "Usability," "Features," "Support," and "Price Index" into this well.

As you add the fields, you'll see the radar chart come to life on your report canvas, displaying a colored polygon for each category.

Customizing and Formatting Your Radar Chart for Clarity

A default chart is a good start, but applying thoughtful formatting is what turns a basic visual into a powerful decision-making tool. Power BI offers a variety of customization options.

Formatting the Data Layer

The "Data colors" and "Data labels" settings let you control the appearance of the polygons themselves.

• Data Colors: Click the new radar chart visual, go to the Format tab (paintbrush icon), and expand the Data colors section. Here, you can change the color of each polygon to match your brand's style or to make certain categories stand out.
• Data Labels: To show the exact value at each point on the chart, turn on Data labels. You can customize the font, size, and display units to make them easy to read without overwhelming the visual.

Adjusting the Legend and Title

A chart is useless if your audience doesn't know what they're looking at.

• Legend: The legend is crucial for a radar chart. In the Format tab, you can reposition the legend (top, bottom, right, etc.) and customize its text to ensure it's easy to read.
• Title: Giving your chart a descriptive title is non-negotiable. Go to General > Title to write a title that clearly explains the chart's purpose, such as "Product Feature Comparison" or "Q3 Marketing Campaign Performance."

Customizing the Grid and Axes

These settings relate to the "web" structure of the chart itself.

• Web: In the Format tab, you'll find a "Web" option. Here, you can decide whether to display the concentric circular lines. In some cases, turning this off can create a cleaner look.
• Axes: Axes settings will typically be within the visual's main options. You might see options to show or hide the axis titles (the labels for each spoke). Keeping them on is usually best for clarity.

Pro Tips for Effective Radar Charts

Building the chart is one thing, building a genuinely insightful one is another. Here are a few tips to take your radar charts to the next level.

Tip 1: Standardize Your Scales

As mentioned earlier, comparing metrics with vastly different scales is a bad practice. If you need to compare "Total Sales" (which could be in the hundreds of thousands) and "Units per transaction" (which might be between 2 and 5), your chart won't work. Before building your visual, you can use Power Query or DAX to create new normalized columns - for instance, creating a "normalized score" from 1-100 for each metric, or calculating values as a percentage of the maximum possible value.

Tip 2: Thoughtfully Order Your Axes

The order in which you arrange the spokes can influence how the chart is interpreted. Placing related metrics next to each other creates logical groupings and can make the "shape" of the data story clearer. For example, in a marketing campaign analysis, you might put awareness metrics (Reach, Impressions) next to each other, followed by engagement metrics (Likes, Comments, Shares).

Tip 3: Don't Forget Interactivity

Remember, this is Power BI! Your radar chart doesn't exist in a vacuum. Place it on a report page with slicers and other visuals. You can set it up so that when a user clicks on a product line in a bar chart, the radar chart filters to show only that product's details. This creates a more dynamic and exploratory experience for your end-users.

Final Thoughts

Radar charts offer a unique and powerful way to visualize multivariate data in Power BI. By starting with properly structured data, using the marketplace visual, and applying smart formatting, you can create compelling reports that highlight performance strengths, weaknesses, and outliers across different categories.

While mastering Power BI visualizations is an incredibly useful skill, it can involve a steep learning curve and hours of manual report building. We built Graphed to simplify this entire process. Instead of hunting for the right visuals and dragging fields, you can connect your data sources in a few clicks and just describe what you want to see - like, "Create a line chart of my website sessions from Google Analytics this year," or "build a sales dashboard from my HubSpot data." We instantly create live, real-time reports so you can get back to making decisions instead of creating charts.