Password Strength Checker
python
def is_strong(password):
msg = 'Password must contain at least'
if len(password) < 8:
return False, msg + " 8 characters"
has_upper = any(c.isupper() for c in password)
has_lower = any(c.islower() for c in password)
has_digit = any(c.isdigit() for c in password)
special_chars = set("!@#$%^&*-_+=")
has_special = any(c in special_chars for c in password)
if not has_upper:
return False, msg + " one uppercase letter."
if not has_lower:
return False, msg + " one lowercase letter."
if not has_digit:
return False, msg + " one digit."
if not has_special:
return False, msg + " one special char (!@#$%^&*-_+=)"
return True, "Password is strong!"
password = input("Enter your password: ")
valid, message = is_strong(password)
print(message)Enhanced Password Strength Checker
python
import re
def is_strong(password):
"""
Check if a password is strong based on multiple criteria.
Returns (is_valid, message) tuple.
"""
# Define criteria and error messages
criteria = [
{
'check': len(password) >= 8,
'message': "at least 8 characters"
},
{
'check': bool(re.search(r'[A-Z]', password)),
'message': "one uppercase letter (A-Z)"
},
{
'check': bool(re.search(r'[a-z]', password)),
'message': "one lowercase letter (a-z)"
},
{
'check': bool(re.search(r'[0-9]', password)),
'message': "one digit (0-9)"
},
{
'check': bool(re.search(r'[!@#$%^&*\-_+=]', password)),
'message': "one special character (!@#$%^&*-_+=)"
}
]
# Check all criteria
failed_checks = [criterion['message'] for criterion in criteria if not criterion['check']]
if failed_checks:
error_msg = "Password must contain:\n" + "\n".join(f"• {msg}" for msg in failed_checks)
return False, error_msg
return True, "✅ Password is strong!"
def get_password_strength_score(password):
"""
Calculate a password strength score (0-100)
"""
score = 0
# Length score (max 25 points)
length = len(password)
if length >= 12:
score += 25
elif length >= 8:
score += 15
elif length >= 6:
score += 5
# Character variety score (max 75 points)
checks = [
bool(re.search(r'[A-Z]', password)), # Uppercase
bool(re.search(r'[a-z]', password)), # Lowercase
bool(re.search(r'[0-9]', password)), # Digits
bool(re.search(r'[!@#$%^&*\-_+=]', password)), # Special chars
len(set(password)) / len(password) > 0.7 # Character diversity
]
score += sum(15 for check in checks if check) # 15 points per met criteria
return min(score, 100)
def suggest_strong_password():
"""
Generate a strong password suggestion
"""
import random
import string
# Define character sets
uppercase = string.ascii_uppercase
lowercase = string.ascii_lowercase
digits = string.digits
special_chars = "!@#$%^&*-_+="
# Generate password with at least one of each type
password = [
random.choice(uppercase),
random.choice(lowercase),
random.choice(digits),
random.choice(special_chars)
]
# Add more random characters to reach 12 characters
all_chars = uppercase + lowercase + digits + special_chars
password.extend(random.choice(all_chars) for _ in range(8))
# Shuffle the password
random.shuffle(password)
return ''.join(password)
def password_strength_checker():
"""
Interactive password strength checker
"""
print("🔐 Password Strength Checker")
print("=" * 40)
print("Requirements:")
print("• At least 8 characters")
print("• Uppercase and lowercase letters")
print("• At least one digit")
print("• At least one special character (!@#$%^&*-_+=)")
print("Type 'quit' to exit\n")
while True:
password = input("Enter your password: ").strip()
if password.lower() in ['quit', 'exit', 'q']:
print("Goodbye! 👋")
break
if not password:
print("Please enter a password!")
continue
# Check password strength
is_valid, message = is_strong(password)
strength_score = get_password_strength_score(password)
print(f"\n📊 Password Analysis:")
print(f"Strength Score: {strength_score}/100")
if is_valid:
print("✅ " + message)
if strength_score >= 80:
print("🎉 Excellent password!")
elif strength_score >= 60:
print("👍 Good password!")
else:
print("💪 Password meets minimum requirements")
else:
print("❌ Password is weak!")
print(message)
# Offer suggestion
if not is_valid or strength_score < 60:
suggest = input("\nWould you like a strong password suggestion? (y/n): ").lower()
if suggest in ['y', 'yes']:
suggested = suggest_strong_password()
print(f"💡 Suggested strong password: {suggested}")
print("(Copy this password and use it securely)")
print("-" * 40)
# Quick test function
def test_passwords():
"""
Test various passwords
"""
test_cases = [
"weak", # Too short
"weakpassword", # No uppercase, digits, or special
"WeakPassword", # No digits or special
"Weak123", # Too short, no special
"Weak123!", # Meets all criteria
"VeryStrongPassword123!@#", # Very strong
"abc123", # No uppercase, no special
"ABC123!", # No lowercase
]
print("🧪 Password Test Cases:")
print("=" * 50)
for password in test_cases:
is_valid, message = is_strong(password)
score = get_password_strength_score(password)
status = "✅ STRONG" if is_valid else "❌ WEAK"
print(f"{password:25} -> {status} (Score: {score}/100)")
if not is_valid:
print(f" Reasons: {message.split(':', 1)[1].strip()}")
if __name__ == "__main__":
# Run interactive checker
password_strength_checker()
# Uncomment to run test cases
# test_passwords()
Simple Version (Similar to Original)
python
import re
def is_strong(password):
"""
Enhanced version of the original function with better error messages
"""
if len(password) < 8:
return False, "Password must contain at least 8 characters"
checks = [
(bool(re.search(r'[A-Z]', password)), "one uppercase letter (A-Z)"),
(bool(re.search(r'[a-z]', password)), "one lowercase letter (a-z)"),
(bool(re.search(r'[0-9]', password)), "one digit (0-9)"),
(bool(re.search(r'[!@#$%^&*\-_+=]', password)), "one special character (!@#$%^&*-_+=)")
]
missing = [msg for check, msg in checks if not check]
if missing:
error_msg = "Password must contain:\n" + "\n".join(f"• {msg}" for msg in missing)
return False, error_msg
return True, "✅ Password is strong!"
# Main program
if __name__ == "__main__":
password = input("Enter your password: ")
valid, message = is_strong(password)
print(message)
Key Improvements:
- Better Error Messages: Shows all missing requirements at once
- Regex Validation: More efficient character checking
- Strength Scoring: Quantitative strength measurement (0-100)
- Password Suggestions: Generates strong password suggestions
- Interactive Interface: User-friendly command-line interface
- Testing Function: Built-in test cases
- Character Diversity: Checks for repeated characters
- Modular Design: Separate functions for different functionalities
Example Output:
text
🔐 Password Strength Checker ======================================== Requirements: • At least 8 characters • Uppercase and lowercase letters • At least one digit • At least one special character (!@#$%^&*-_+=) Type 'quit' to exit Enter your password: weakpass 📊 Password Analysis: Strength Score: 20/100 ❌ Password is weak! Password must contain: • one uppercase letter (A-Z) • one digit (0-9) • one special character (!@#$%^&*-_+=) Would you like a strong password suggestion? (y/n): y 💡 Suggested strong password: X7g!k9@Lp2$q
This enhanced version provides much more detailed feedback and helpful features while maintaining the same core functionality as the original program!
