A Radar Chart, also known as a web or spider chart, is a useful graph for plotting one or more data series over multiple common variables. This articles will provide an overview of how and when to use a Radar Chart for your data.
Use Cases
Radar charts are essentially an area/line chart, wrapped around an axis. This type of chart is best used when highlighting comparisons and discovering outliers in your data.
The first part of a Radar Chart to understand is the axis and scale line. This is the vertical line that starts at the 0 point on your graph. The grid lines for your graph will appear from the scale line. For example, if your scale line goes from 0-50 and you had 5 grid lines total, your first line from the center would be 10, your second grid line would be 20, and so on, with the center being 0. Each variable is assigned an axes and is arranged radially with equal distance between them.
Let us dive into an example to help illustrate how to use the Radar Chart. Say you have 5 departments in your company: Sales, Marketing, Product, Support, and Engineering. At the beginning of the quarter you allocate your budget into each department, like the below table illustrates.
At the end of the quarter you use Grow to compare the actual vs. budgeted spending and get the below chart.
You can easily see you were spot on in your budgeting for Sales, but spent more in Support. While Radar charts are, albeit, cool looking charts, they have a pretty specific use case and can be more difficult to read then Column or Bar charts.
Building a Radar Chart
The most important first step in creating any chart is to have your data prepped and ready to go.
When you are ready to start charting, switch the Metric Builder into Chart mode by select the Chart tab on the top of your screen. On the right hand side you will see a drop down menu displaying the current selected chart type, which is, by default, a Column chart. Once selected, you will see all chart types along with a visual representation of each. Select the Radar chart in the Other section.
Once you have your chart selected you are able to select your Data Series and Labels.
It is important you do not select your Data Series first then select your chart type, as some chart types are not compatible with each other and you may lose your selections.
Now that you have selected your Data Series and your Labels you can further customize your Radar chart by selecting Display. We recommend adding a Legend if you have more than one Data Series, to help users interpret the data. Additionally, you can change the color, add labels and format your numbers by selecting the Data Series dropdown.
Best Practices
Display a Legend with Two or More Data Series
We highly recommend using a Legend anytime you have more than one Data Series plotted in a chart.
Six or Less Variables
Having too many polygons can make your Radar Chart difficult to read and cluttered. If you have variables that are very similar, consider putting them in the same category or switch to a chart type that would be better suited for 7+ variables.