How to Show Gridlines on Matplotlib Plots?

In this article, we will see how we can add gridlines to a matplotlib graph and various configurable parameters that can be used in Python.

Example:

 Create a matplotlib plot using sample data.

Python

# Importing the library
import matplotlib.pyplot as plt

# Define X and Y data points
X = [12, 34, 23, 45, 67, 89]
Y = [1, 3, 67, 78, 7, 5]

# Plot the graph using matplotlib
plt.plot(X, Y)

# Function to view the plot
plt.show()

Output

grid()

The grid() method is used to define a grid in a matplotlib graph. The syntax is given by –

Syntax:

matplotlib.pyplot.grid(b=None, which=’major’, axis=’both’, **kwargs)

Parameters:

• b: bool or None, optional: Whether to show the grid lines. If any kwargs are supplied, it is assumed you want the grid on and b will be set to True. If b is None and there are no kwargs, this toggles the visibility of the lines.
• which: {‘major’, ‘minor’, ‘both’}, optional: The grid lines to apply the changes on.
• axis: {‘both’, ‘x’, ‘y’}, optional: The axis to apply the changes on.
• **kwargs: Line2D properties: Define the line properties of the grid

Example 1: Default Gridlines

Python

# Importing the library
import matplotlib.pyplot as plt

# Define X and Y data points
X = [12, 34, 23, 45, 67, 89]
Y = [1, 3, 67, 78, 7, 5]

# Plot the graph using matplotlib
plt.plot(X, Y)

# Add gridlines to the plot
plt.grid(b=True)
# `plt.grid()` also works

# Function to view the plot
plt.show()

Output

Example 2: Apply Gridlines to  x- axis

In the cases, where we would want to see only the vertical or horizontal gridlines, we can make use of the `axis` parameter. To view only vertical gridlines –

Syntax:

plt.grid(b=True, axis='x')

Python3

# Importing the library
import matplotlib.pyplot as plt

# Define X and Y data points
X = [12, 34, 23, 45, 67, 89]
Y = [1, 3, 67, 78, 7, 5]

# Plot the graph using matplotlib
plt.plot(X, Y)

# Add gridlines to the plot
plt.grid(b=True, axis='x')
# `plt.grid()` also works

# Function to view the plot
plt.show()

Output:

Example 3: Apply Gridlines to y-axis

In the cases, where we would want to see only the vertical or horizontal gridlines, we can make use of the `axis` parameter. To view only horizontal gridlines –

Syntax:

 plt.grid(b=True, axis='y')

Python3

# Importing the library
import matplotlib.pyplot as plt

# Define X and Y data points
X = [12, 34, 23, 45, 67, 89]
Y = [1, 3, 67, 78, 7, 5]

# Plot the graph using matplotlib
plt.plot(X, Y)

# Add gridlines to the plot
plt.grid(b=True, axis='y')
# `plt.grid()` also works

# Function to view the plot
plt.show()

Output:

Example 4: Provide a linestyle and linewidth

We have seen the gridlines being a solid lines. We can change this to view a different line-style like dashes using an argument `linestyle` or `ls`. Similarly, we can change the thickness of the gridlines using the argument `linewidth`. These arguments are provided as part of the keyword arguments and can be viewed in the document link.

To provide a line style –

Syntax:

plt.grid(linestyle='--')

Python3

# Importing the library
import matplotlib.pyplot as plt

# Define X and Y data points
X = [12, 34, 23, 45, 67, 89]
Y = [1, 3, 67, 78, 7, 5]

# Plot the graph using matplotlib
plt.plot(X, Y)

# Add gridlines to the plot
plt.grid(linestyle='--')
# `plt.grid()` also works

# Function to view the plot
plt.show()

Output:

.

Example 5: Change color of the Gridlines

The keyword argument `color` can be used to define a different color to the plot.

Syntax:

plt.grid(linestyle, color)

Python3

# Importing the library
import matplotlib.pyplot as plt

# Define X and Y data points
X = [12, 34, 23, 45, 67, 89]
Y = [1, 3, 67, 78, 7, 5]

# Plot the graph using matplotlib
plt.plot(X, Y)

# Add gridlines to the plot
plt.grid(linestyle='--', color='pink')
# `plt.grid()` also works

# Function to view the plot
plt.show()

Output: