What Is a Treemap Chart?

A treemap chart is a data visualization tool that uses nested rectangles to display the relative proportions of items in a dataset. The rectangles are proportionally sized according to the value of the data item they contain, with the deepest rectangle representing the largest value. The rectangles are also typically colored to indicate the category of data they represent.

Treemap charts can be used to compare and contrast data items, or to show how data is distributed. This makes it easy to see how the values are distributed and identify any outliers. Treemap charts are especially useful for displaying hierarchical data, such as the results of a customer survey broken down by age group or income level. Understanding this data could help organizations make improvements to their customer outreach or their digital marketing strategies.

Here’s a simple way to break it down. If you’ve ever wondered “what is a treemap chart?” it’s essentially an easy way to display complex data in a tree-like format with branches and subbranches that can be understood at a glance. This allows users to quickly and easily see the relative proportions of different data sets. Treemap charts can be used to compare data sets, track changes over time, or visualize hierarchies of any kind.

Sections of a Treemap


Before you can create your own treemap chart effectively, it’s important to understand the main sections of a treemap and their intended uses. It’s also important to understand that a treemap is generally intended for visualizing huge amounts of complex data that would be difficult or impossible to capture in other chart options like bar charts or pie charts.

Plot Area

Your plot area is the main visualization of the treemap where the rectangles are. This section is made up of a few subsections, starting with the root node of each subsection. The root node appears at the top and contains all the other nodes. As you progress down the treemap, you’ll start to see the children nodes, grandchildren nodes, great-grandchildren nodes, etc. until you reach the bottom of the chart.

Chart Title

This is simply your title that appears above the plot area. Its only purpose is to help viewers understand the purpose of your treemap chart.

The Legend

This information helps viewers distinguish one data set on the treemap from another. Your legend will generally come with a color key to represent your different categories or data sets.

How to Create a Treemap Chart


The data for a treemap chart can be organized in any way that makes sense for the topic at hand. For example, a treemap chart might show the sales revenue for different product categories, the distribution of a company’s employees by department, or the percentage of a city’s population that lives in different neighborhoods.

To create a treemap chart, you’ll first need to decide what data you want to include and how you want to organize it. Here are the steps you’ll need to follow to create a treemap chart in Excel.

  1. Create a table with the hierarchical data that you want to visualize.
  2. Select the data in the table and create a treemap chart by clicking on the “treemap” button in the Charts group on the Insert tab.
  3. In the treemap chart, select the data that you want to visualize, and modify the settings as needed.
  4. Click on the “Finish” button to create the chart.

As you can see, the treemap chart is a great way to visualize hierarchical data. You can easily see the branch and level of the data, and the size of the rectangle is proportional to the value of the data item.