How to Fill Between Multiple Lines in Matplotlib? Last Updated : 23 Jul, 2025 Comments Improve Suggest changes 3 Likes Like Report With the use of the fill_between() function in the Matplotlib library in Python, we can easily fill the color between any multiple lines or any two horizontal curves on a 2D plane. Syntax: matplotlib.pyplot.fill_between(x, y1, y2=0, where=None, step=None, interpolate=False, *, data=None, **kwargs) Example 1: Color between the curve of the mathematical function f(x)=sin(x) Python3 import pylab as plt import numpy as np x = np.arange(0.0, 2, 0.01) y1 = np.sin(2 * np.pi * x) y2 = 0.8 * np.sin(4 * np.pi * x) fig, (ax1, ax2, ax3) = plt.subplots( 3, 1, sharex=True, figsize=(6, 6)) ax1.fill_between(x, y1) ax1.set_title('fill between y1 and 0') ax2.fill_between(x, y1, 1) ax2.set_title('fill between y1 and 1') ax3.fill_between(x, y1, y2) ax3.set_title('fill between y1 and y2') ax3.set_xlabel('x') fig.tight_layout() Output: Example 2: Color between the curve of the mathematical function f(x)=cos(x) and f(x)=exp(x) :- Python3 import pylab as plt import numpy as np X = np.linspace(0, 3, 200) Y1 = X**2 + 3 Y2 = np.sin(X) Y3 = np.cos(X) plt.plot(X, Y1, lw=4) plt.plot(X, Y2, lw=4) plt.plot(X, Y3, lw=4) plt.fill_between(X, Y1, Y2, color='k', alpha=.5) plt.fill_between(X, Y1, Y3, color='y', alpha=.5) plt.show() Output: Example 3: Color the Rhombus :- Python3 import matplotlib.pyplot as plt x = [1, 2, 1, 0] y = [2, 1, 0, 1] plt.fill(x, y) plt.show() Output: Create Quiz Comment G geetansh044 Follow 3 Improve G geetansh044 Follow 3 Improve Article Tags : Python Python-matplotlib Explore Python FundamentalsPython Introduction 2 min read Input and Output in Python 4 min read Python Variables 4 min read Python Operators 4 min read Python Keywords 2 min read Python Data Types 8 min read Conditional Statements in Python 3 min read Loops in Python - For, While and Nested Loops 5 min read Python Functions 5 min read Recursion in Python 4 min read Python Lambda Functions 5 min read Python Data StructuresPython String 5 min read Python Lists 4 min read Python Tuples 4 min read Python Dictionary 3 min read Python Sets 6 min read Python Arrays 7 min read List Comprehension in Python 4 min read Advanced PythonPython OOP Concepts 11 min read Python Exception Handling 5 min read File Handling in Python 4 min read Python Database Tutorial 4 min read Python MongoDB Tutorial 3 min read Python MySQL 9 min read Python Packages 10 min read Python Modules 3 min read Python DSA Libraries 15 min read List of Python GUI Library and Packages 3 min read Data Science with PythonNumPy Tutorial - Python Library 3 min read Pandas Tutorial 4 min read Matplotlib Tutorial 5 min read Python Seaborn Tutorial 3 min read StatsModel Library - Tutorial 3 min read Learning Model Building in Scikit-learn 6 min read TensorFlow Tutorial 2 min read PyTorch Tutorial 6 min read Web Development with PythonFlask Tutorial 8 min read Django Tutorial | Learn Django Framework 7 min read Django ORM - Inserting, Updating & Deleting Data 4 min read Templating With Jinja2 in Flask 6 min read Django Templates 5 min read Build a REST API using Flask - Python 3 min read Building a Simple API with Django REST Framework 3 min read Python PracticePython Quiz 1 min read Python Coding Practice 1 min read Python Interview Questions and Answers 15+ min read Like