Password Strength Checker
Our free password strength checker analyzes your passwords to evaluate their security level. Get detailed feedback on password length, character variety, complexity, and common patterns. This tool helps you understand password security and identify areas for improvement to protect your online accounts from unauthorized access.
Important Notes:
- Password analysis is performed entirely in your browser - your password never leaves your device.
- Strength estimates are based on common attack methods and may vary in real-world scenarios.
- This tool checks for common patterns and weak passwords but cannot detect all possible vulnerabilities.
- For maximum security, use unique passwords for each account and enable two-factor authentication.
- Regular password updates are recommended, especially for sensitive accounts.
- Consider using a password manager to generate and store strong, unique passwords.
Understanding Password Strength: A Complete Guide
Password strength is a measure of how effectively a password resists guessing and brute-force attacks. Understanding what makes a password strong helps you create better security for your online accounts.
What Makes a Password Strong?
A strong password combines multiple factors including length, character variety, unpredictability, and uniqueness. The most important factor is length, followed by randomness and character diversity.
Key Factors in Password Strength
- Length: Longer passwords are exponentially harder to crack
- Character variety: Mix of uppercase, lowercase, numbers, symbols
- Unpredictability: Avoid dictionary words and common patterns
- Uniqueness: Different password for each account
- No personal info: Avoid names, birthdates, addresses
- Randomness: Truly random passwords are strongest
Common Weak Password Patterns
- Dictionary words (password, admin, welcome)
- Sequential patterns (123456, abcdef, qwerty)
- Personal information (name, birthdate, pet name)
- Repeated characters (aaaaaa, 111111)
- Simple substitutions (P@ssw0rd, P@ssword123)
- Common patterns (Password1, Welcome123)
How Password Strength is Calculated
Password strength is evaluated based on multiple criteria including length, character variety, pattern analysis, and entropy calculations.
Strength Calculation Factors
Length Analysis
- Passwords under 8 characters: Very Weak
- 8-11 characters: Weak to Moderate
- 12-15 characters: Strong
- 16+ characters: Very Strong
Character Variety
- Only lowercase: Weak
- Lowercase + numbers: Moderate
- Mixed case + numbers: Strong
- All character types: Very Strong
Frequently Asked Questions
What is a good password strength score?
A good password should score at least "Strong" (80%+) on our strength meter. For sensitive accounts like banking or email, aim for "Very Strong" (90%+). The score is based on length, character variety, unpredictability, and resistance to common attacks.
How long should my password be?
For general accounts, aim for at least 12 characters. For sensitive accounts, consider 16-20 characters. Each additional character exponentially increases password strength. While some sites limit password length, most modern services accept longer passwords.
Does this tool store my password?
No, absolutely not. All password analysis is performed entirely in your browser using JavaScript. Your password never leaves your device and is never transmitted to any server. You can verify this by checking your browser's network activity.
What makes a password weak?
Common weak password characteristics include: short length (under 8 characters), dictionary words, personal information, sequential patterns, repeated characters, common substitutions, and lack of character variety. Our tool checks for all these patterns and provides specific recommendations.