Password_Generator

Password Generator & Strength Analyzer

A Python CLI tool that generates secure, customizable passwords and evaluates their strength using entropy estimation.

Features

• Generate cryptographically random passwords of arbitrary length
• Choose which character types to include:
  • Uppercase letters (A-Z)
  • Lowercase letters (a-z)
  • Numbers (0-9)
  • Symbols (!@#$%^&* etc.)
• Guarantees at least one character from each selected type
• Strength rating with visual star display (★☆☆☆☆ – ★★★★★)
• Entropy estimation in bits

Requirements

• Python 3.6+

Usage

python3 password_generator.py

Follow the interactive prompts:

==============================
   Password Generator
==============================

Length: 16
Include Uppercase? Y/N: y
Include Lowercase? Y/N: y
Include Numbers? Y/N: y
Include Symbols? Y/N: y

------------------------------
Generated Password:

  /bA8h4fusM({l3j[

Strength:  ★★★★★ Very Strong
Entropy:   104.9 bits
Length:    16 chars
Pool:      94 characters
Includes:  Uppercase, Lowercase, Numbers, Symbols
------------------------------

Strength Tiers

Entropy (bits)	Rating	Stars
< 28	Weak	★☆☆☆☆
28 – 35	Fair	★★☆☆☆
36 – 59	Strong	★★★☆☆
60 – 79	Very Strong	★★★★☆
≥ 80	Very Strong	★★★★★

A password with ≥ 60 bits of entropy is considered resistant to brute-force attacks.

How It Works

1. Character pool — builds a pool from the selected character types using Python's string module.
2. Guaranteed placement — one random character from each selected type is placed first, then the remaining slots are filled randomly from the full pool.
3. Shuffle — the final list is shuffled so the guaranteed characters aren't always at the start.
4. Entropy — calculated as length × log₂(pool_size). Higher entropy = stronger password.