How to Count the Number of Rows in a CSV File Using Python

This tutorial will guide you on how to count the number of rows in a CSV file using Python. The Python programming language provides several libraries to make working with CSV files easier, and we will learn how to leverage them effectively.

What You’ll Need

Before you start, make sure you have Python installed on your system. If not, you can download it from the official Python website. You will also need a CSV file.

For this tutorial, we will use the following data as an example:

Name,Age,Gender
John,23,Male
Mary,32,Female
Paul,28,Male

Step 1: Import the Required Library

You’ll need to import the csv library, which is built into Python – you don’t need to install anything special.

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import csv

Step 2: Open and Read the CSV File

Use the open() function to open the file and the csv.reader() function to get a reader object. Then convert it into a list of rows.

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with open('filename.csv', 'r') as file:
    reader = csv.reader(file)
    rows = list(reader)

Step 3: Count the Number of Rows

The length of the list of rows is equal to the number of rows in the CSV file.

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num_rows = len(rows)
print('Number of rows:', num_rows)

Full Code

Here is the complete Python program based on the steps described above.

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import csv
 
with open('filename.csv', 'r') as file:
    reader = csv.reader(file)
    rows = list(reader)
 
num_rows = len(rows)
print('Number of rows:', num_rows)

If we run the Python program with the CSV file described at the beginning, we will get the following output:

Number of rows: 4

Conclusion

By following this tutorial, you should be able to count the number of rows in a CSV file using Python. The Python CSV module provides a straightforward and efficient way to read and manipulate CSV files. More details about the csv module can be found in the official Python documentation.