Password Strength
Check how strong your password is
How to Use Password Strength
- 1Type your password in the input
- 2See the strength score and color indicator
- 3Read the feedback to improve your password
About Password Strength
Password Strength Checker analyzes your password in real time and gives you a detailed score based on length, character variety, predictable patterns, and common password lists. The result includes a strength rating (Weak, Fair, Good, or Strong) along with specific feedback on how to improve it.
Short passwords, dictionary words, predictable substitutions (like p@ssw0rd), and keyboard patterns dramatically reduce security — this tool explains exactly which weaknesses your password has. Everything runs entirely in your browser — your password is never sent to any server.
The checker uses an entropy-based scoring model similar to the widely trusted zxcvbn library, giving you realistic crack time estimates rather than vague quality labels.
Key Features of Password Strength
- Real-time strength analysis as you type
- Strength rating: Weak, Fair, Good, or Strong
- Estimated crack time displayed in human-readable format
- Specific feedback on what makes the password weak
- Detects dictionary words, keyboard patterns, and common substitutions
- Character class analysis: lowercase, uppercase, numbers, symbols
- Works entirely in-browser — password is never transmitted
- Visual strength indicator for instant at-a-glance assessment
Examples
Check a commonly used weak password
See why passwords that seem complex are actually weak due to predictable patterns.
Input
P@ssw0rd
Output
Strength: Weak — common pattern detected, crack time: less than 1 second
Check a strong random passphrase
Verify that a longer random passphrase achieves a high strength score.
Input
correct-horse-battery-staple-42
Output
Strength: Strong — estimated crack time: centuries
Common Use Cases
- Checking passwords before setting them for personal accounts
- Verifying that organization-wide passwords meet minimum security standards
- Teaching employees about password security in security awareness training
- Testing passwords generated by password managers before adoption
- Auditing existing passwords to identify those that need to be changed
- Demonstrating entropy-based strength analysis to security audiences
Troubleshooting
A long password still scores as Weak
Solution
Length alone is not enough. Passwords of dictionary words or repeated characters score poorly regardless of length. Add uppercase letters, numbers, and symbols.
Adding symbols like @ for a does not improve the score much
Solution
Common substitutions (a→@, e→3, o→0) are well-known to attackers. Use truly random symbols in unpredictable positions instead.
Score seems too strict
Solution
This tool uses entropy-based scoring which is more strict than simple length+character-type checks. Consider using a password manager to generate strong passwords.
Frequently Asked Questions
Is my password stored or sent anywhere?
No. Analysis happens entirely in your browser. Your password is never transmitted to any server, not logged, and not stored.
What makes a password strong?
Strong passwords are long (12+ characters), contain a mix of uppercase, lowercase, numbers, and symbols, are not based on dictionary words, and do not use predictable patterns.
Why does my complex-looking password still score low?
Common substitutions (@ for a, 3 for e) and dictionary words with added numbers are well-known attack patterns. The checker identifies these and reduces the score.
What does "crack time" mean?
Crack time is an estimate of how long a modern computer would take to guess the password through brute-force. It assumes an offline attack using current hardware.
Is a 12-character password long enough?
12 characters with full character variety is considered strong against current brute-force capabilities. 16+ characters is recommended for sensitive accounts.
Should I use a passphrase instead of a password?
Yes, passphrases (multiple random words) can be both strong and memorable. A 4–5 word passphrase typically achieves high entropy.
How does this differ from website strength meters?
Many website strength meters use simple rules and give misleadingly high scores to weak passwords like "Password1!". This tool uses entropy-based analysis.
What should I do if my password scores weak?
Use the Password Generator tool to create a strong random password. Enable two-factor authentication wherever possible as a complementary security layer.