Password Strength Checker
Check password strength instantly with real-time security analysis. Test password complexity, length, and vulnerability to common attacks.
What makes a strong password?
A strong password has at least 12 characters, includes uppercase and lowercase letters, numbers, and special characters, and avoids common words or patterns.
Why is password length important?
Longer passwords are exponentially harder to crack. Each additional character increases the number of possible combinations dramatically.
Should I use a passphrase?
Yes, passphrases (multiple random words) are both strong and memorable. For example: "correct-horse-battery-staple".
Is my password stored anywhere?
No, all analysis is done locally in your browser. Your password is never sent to any server.
How does this password checker work?
It analyzes your password's length, character variety, common patterns, and dictionary words to calculate strength and estimated crack time.
What is password entropy?
Password entropy measures the randomness or unpredictability of a password, expressed in bits. Higher entropy means a stronger, harder-to-guess password.
How long does it take to crack a password?
Crack time depends on password length, complexity, and attacker resources. A strong 12+ character password can take years or centuries to crack.
Should I use special characters in my password?
Yes, special characters (!@#$%^&*) significantly increase password strength by expanding the character set attackers must try.
What are common password mistakes to avoid?
Avoid using personal information, dictionary words, sequential numbers, repeated characters, or common patterns like "123456" or "password".
How often should I change my password?
Change passwords immediately if compromised, otherwise update critical passwords every 6-12 months and use unique passwords for each account.
Is this tool secure to use?
Yes, all password analysis happens locally in your browser using client-side JavaScript. No data is transmitted to any server.
Can this checker detect weak passwords?
Yes, it identifies weak patterns, common passwords, dictionary words, and predictable sequences that attackers commonly exploit.
How to Use Password Strength Checker
Password Strength Checker analyses your password in real time for length, complexity, and resistance to common attacks. Everything runs locally in your browser, so what you type is never uploaded.
- Click the input field that shows the placeholder 'Enter your password...'.
- Type the password you want to test and watch the strength rating update live as you type.
- Review the analysis of length, character variety, and vulnerability to dictionary or brute-force attacks.
- Improve the password by adding length or mixing character types, and see the score change instantly.
- Clear the field when you finish testing so the password is not left in the form.
Compare variants while you type: 'p@ssw0rd' scores better than 'password' but still cracks fast — length matters more than clever substitutions.
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