Build a Secure Password Generator in Python (Step-by-Step) 2025

Passwords protect your online accounts, but many people still use weak and easy-to-guess ones. As a developer, learning how to create a secure password generator in Python is a fun and practical project that improves your coding skills while teaching you about cybersecurity best practices.

In this tutorial, we’ll build a Python password generator that creates strong, random, and customizable passwords.

🔹 Why Build a Password Generator?

• Weak passwords cause most online security breaches.

• Many users recycle passwords across multiple platforms.

• As a Python beginner, this project helps you practice:

  • Using Python’s built-in libraries (secrets, string)

  • Writing reusable functions

  • Building both a CLI tool and optional GUI app

By the end of this tutorial, you’ll have a working password generator that you can use personally or share with others.

🔹 Features of Our Python Password Generator

✅ Generates strong random passwords
✅ Supports lowercase, uppercase, digits, and symbols
✅ User chooses password length
✅ Ensures at least one character from each selected set
✅ Secure randomness using Python’s secrets module

🔹 Step 1: Import Python Libraries

import secrets
import string

• secrets → provides cryptographically secure random numbers.

• string → gives us predefined sets of characters (letters, digits, etc.).

🔹 Step 2: Build the Password Generator Function

def generate_password(length=16, use_lower=True, use_upper=True, use_digits=True, 
use_symbols=True):
    characters = ""
    if use_lower:
        characters += string.ascii_lowercase
    if use_upper:
        characters += string.ascii_uppercase
    if use_digits:
        characters += string.digits
    if use_symbols:
        characters += "!@#$%^&*()-_=+[]{};:,.<>/?"
    
    if not characters:
        raise ValueError("You must enable at least one character set.")
    
    password = "".join(secrets.choice(characters) for _ in range(length))
    return password

🔹 Step 3: Test Your Password Generator
print("Generated Password:", generate_password(20))

✅ Output Example:
Generated Password: A9&kPz1!Lf2@VmXc*Hq