How to count number of instances of a class in Python?

Last Updated : 29 Dec, 2020

Instances of a class mean the objects created for a particular class. A single class can have multiple objects of it. Here, we will find the count of the number of instances of a class in Python.

Approach:

Whenever an object is created, the constructor of that particular class is called.
Constructor is a function whose name is the same as that of class name and it doesn’t have any return type. A constructor is used to initialize the variables of a class.
Whenever a constructor is called which means a new object is created, we just have to increment a counter that will keep track of the no. of objects that particular class has.

Below is the implementation:

Python3

# code 
class geeks: 
    
    # this is used to print the number 
    # of instances of a class 
    counter = 0
  
    # constructor of geeks class 
    def __init__(self): 
        
        # increment 
        geeks.counter += 1
  
  
# object or instance of geeks class 
g1 = geeks() 
g2 = geeks() 
g3 = geeks() 
print(geeks.counter) 

Output:

P

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