🔐 Password Strength Checker

A simple, CLI-based Python tool to evaluate password strength based on entropy. It analyzes the variety and length of characters in a password and provides feedback and recommendations accordingly.

🚀 Features

• Calculates password entropy using character pool and length.
• Classifies passwords as:
  • ❌ Too Weak
  • ⚠️ Weak
  • 🟡 Decent
  • ✅ Strong
• Offers actionable recommendations for improving password strength.
• No internet or external dependencies (other than Python standard library).

📖 What is Entropy?

Entropy is a measure of unpredictability or randomness. In the context of passwords, higher entropy means it's harder for attackers to guess or brute-force your password.

Formula used:

Entropy = log2(pool_size) × password_length

💻 How to Use

1. Clone the Repository

git clone https://github.com/sinan-ashraf/password-checker.git
cd password-checker

2. Run the Script

python password_checker.py

You’ll see a prompt: Enter password: — just type in any password to test it.

📝 Example

Enter password: hello123
✗ Weak password (35.4 bits entropy)
Decent, but could be stronger.

Enter password: @G7vLp#2qR
✓ Strong password (64.2 bits entropy)
Strong password!

🔧 Customization

You can change the minimum acceptable entropy in the code:

MIN_ENTROPY = 30

Recommended values:

• 20+: Basic
• 30+: Good
• 40+: Strong