How to change the font size of the Title in a Matplotlib figure ?

Last Updated : 26 Aug, 2022

In this article, we are going to discuss how to change the font size of the title in a figure using matplotlib module in Python.

As we use matplotlib.pyplot.title() method to assign a title to a plot, so in order to change the font size, we are going to use the font size argument of the pyplot.title() method in the matplotlib module.

Example 1: Change the font size of the Title in a Matplotlib

In this example, we are plotting a ReLU function graph with fontsize=40.

Python3

# importing module
import matplotlib.pyplot as plt

# assigning x and y coordinates
x = [-5, -4, -3, -2, -1, 0, 1, 2, 3, 4, 5]
y = []

for i in range(len(x)):
    y.append(max(0, x[i]))

# depicting the visualization
plt.plot(x, y, color='green')
plt.xlabel('x')
plt.ylabel('y')

# displaying the title
plt.title("ReLU Function",
          fontsize = 40)

Output:

Example 2: Set the figure title font size in matplotlib

In this example, we are plotting a sinewave graph with set_size(20).

Python3

import numpy as np
import matplotlib.pyplot as plt

xaxis=np.linspace(0,5,100)
yaxis= np.sin(2 * np.pi * x)

axes = plt.gca()
plt.plot(xaxis, yaxis)
axes.set_title('Plot of sinwave graph')
axes.set_xlabel('X - Axis')
axes.set_ylabel('Y - Axis')

axes.title.set_size(20)

plt.show()

Output:

change the font size of the title in a figure using matplotlib

Example 3: Set the figure title font size in matplotlib

In this example, we are plotting a pie graph with fontsize=10.

Python3

# importing modules
from matplotlib import pyplot as plt

# assigning x and y coordinates
foodPreference = ['Vegetarian', 'Non Vegetarian',
                                'Vegan', 'Eggitarian']

consumers = [30, 100, 10, 60]

# depicting the visualization
fig = plt.figure()
ax = fig.add_axes([0, 0, 1, 1])
ax.axis('equal')
ax.pie(consumers, labels = foodPreference,
       autopct='%1.2f%%')

# displaying the title
plt.title("Society Food Preference",
          fontsize = 10)