Python: how to evaluate password entropy

Python: how to evaluate password entropy

Python is a popular programming language that can be used to evaluate password entropy. First, we need to define a function that calculates entropy.

Password security is of paramount importance to protect sensitive data. A good password should be complex enough that an attacker can't easily guess it. One of the indicators of a strong password is entropy, which represents the amount of uncertainty or randomness present in the password.

Python is a popular programming language that can be used to evaluate password entropy. First, we need to define a function that calculates entropy. A common formula used to calculate the entropy of a password is:


H = log2(N^L)

Where H is the entropy, N is the number of different characters used in the password, and L is the length of the password.

Here's an example of a Python function that calculates the entropy of a password:


import math

def entropy(password):
    char_set = set(password)
    char_set_size = len(char_set)
    password_size = len(password)
    entropy = math.log2(char_set_size ** password_size)
    return entropy

This function takes a password as input and returns the entropy. It uses Python's math module to calculate the base 2 logarithm. It also uses the set() function to get the set of unique characters in the password, which is then used to calculate the number of different characters in the password.

To test the function, we can enter an example password:


password = "Jh#(B8y#fz&W9@p"
print(entropy(password))

This should return a value of around 94.8, indicating that the password has very high entropy and is therefore very difficult to guess.

In conclusion, Python can be used to evaluate password entropy efficiently. The function shown above is a simple way to calculate the entropy of a password and can be used to check the strength of passwords.