⏱ Quick start

The scatterplot() function of seaborn also allows to build bubble charts. Indeed, it has a size parameter that controls circle size according to a numeric variable of the dataset.🔥

Basic bubble chart with Python and Seaborn.

# libraries
import matplotlib.pyplot as plt
import seaborn as sns
from gapminder import gapminder # data set

# data
data = gapminder.loc[gapminder.year == 2007]

# use the scatterplot function to build the bubble map
sns.scatterplot(data=data, x="gdpPercap", y="lifeExp", size="pop", legend=False, sizes=(20, 2000))

# show the graph
plt.show()

Bubble plot with Seaborn

Seaborn is the best tool to quickly build a quality bubble chart. The example below are based on the famous gapminder dataset that shows the relationship between gdp per capita, life expectancy and population of world countries.

The examples below start simple by calling the scatterplot() function with the minimum set of parameters. It then show how to change bubble colors to represent a fourth variable, improve general styling, tweak the legend and more.

Basic bubble chart with Python and Seaborn.

Bubble plot with Matplotlib

As for scatterplots, Matplotlib will help us build a bubble plot thanks to the the plt.scatter() function. This function provides a s parameter allowing to pass a third variable that will be mapped to the markers size.

Most basic bubble plot with Python and Matplotlib

Bubble plot customization: color

Bubble plot customization: shape

Bubble plot customization: size

Bubble plot customization: stroke

Note that it is a common practice to map a fourth variable to the markers colors thanks to the c parameter. This way, you're now looking a 4 variables in the same time, on the same chart 🎉.

A bubble chart width 4 dimensions: x, y, size & color

Bubble plot of the gapminder dataset

A very common task when it comes to bubble chart is to add a proper legend to explain what colors and sizes mean. The blogpost below is a deep-dive into matplotlib legend and should be of great help for this

Legend customization: how to control location, add a background, customize labels and markers and more

Best python bubble chart examples

The web is full of astonishing charts made by awesome bloggers, (often using R). The Python graph gallery tries to display (or translate from R) some of the best creations and explain how their source code works. If you want to display your work here, please drop me a word or even better, submit a Pull Request!

Learn how to use the adjustText library to add many labels with no overlaps.

Scatterplot with regression fit, group colors and non-overlapping labels.

Dark mode scatterplot with custom annotations, title and explanations. All of that with a very good appearance!

A scatter plot with images inside each marker to provide additional context

A scatter plot with custom annotations and colors, with some markers being circled