Load CSV data into List and Dictionary using Python

Load CSV data into List and Dictionary using Python

Last Updated : 28 Apr, 2025

Prerequisites: Working with csv files in Python

CSV (Comma Separated Values) is a simple file format used to store tabular data, such as a spreadsheet or database. CSV file stores tabular data (numbers and text) in plain text. Each line of the file is a data record. Each record consists of one or more fields, separated by commas. The use of the comma as a field separator is the source of the name for this file format. CSV raw data is not utilizable in order to use that in our Python program it can be more beneficial if we could read and separate commas and store them in a data structure. We can convert data into lists or dictionaries or a combination of both either by using functions csv.reader and csv.dictreader or manually directly and in this article, we will see it with the help of code.

Example 1: Loading CSV to list

CSV File:

Load CSV data into List and Dictionary

Python3

# importing module 
import csv
 
# csv fileused id Geeks.csv
filename="Geeks.csv"

# opening the file using "with"
# statement
with open(filename,'r') as data:
   for line in csv.reader(data):
            print(line)
        
# then data is read line by line 
# using csv.reader the printed 
# result will be in a list format 
# which is easy to interpret

Output:

Load CSV data into List and Dictionary

Example 2: Loading CSV to dictionary

Python3

import csv

filename ="Geeks.csv"

# opening the file using "with"
# statement
with open(filename, 'r') as data:
  for line in csv.DictReader(data):
      print(line)

Output:

Load CSV data into List and Dictionary

Example 3: Loading CSV into list of Dictionaries

Python3

from csv import DictReader
# open file in read mode
with open("geeks.csv", 'r') as f:
    
    dict_reader = DictReader(f)
    
    list_of_dict = list(dict_reader)
  
    print(list_of_dict)

Output:

Load CSV data into List and Dictionary

Load CSV data into List and Dictionary using Python

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