Password Strength Analyser
CryptoEstimate password strength, entropy bits and crack time using zxcvbn analysis. Spot weak passwords before they reach production systems and accounts.
a-z password-strength.uppercase A-Z password-strength.digits 0-9 password-strength.symbols !@#$About Password Strength Analyser
Whether a password is truly strong is hard to judge by rules like "contains upper, lower, digit, symbol." This tool analyzes password strength locally in your browser, combining length, character diversity, and common weak-pattern detection to give a score and an estimated crack time, so you can see the gap clearly. The whole analysis happens locally; the password you type is neither logged nor uploaded, so you can safely test a real passphrase you are setting or calibrate the threshold for a signup form's strength meter. Tip: Bookmark this tool for quick access whenever you need to generate keys or hashes. All processing happens locally in your browser — no data upload, so it is safe to use with sensitive material.
How to Use
- Open the Password Strength tool
- Enter the password to test
- View real-time strength rating (Very Weak to Very Strong)
- Check entropy, character set size, and estimated crack time
- Optimize your password based on the analysis
Use Cases
- Audit your own password — Estimate how long a new password resists brute force before deciding whether to lengthen it.
- Calibrate frontend thresholds — Tune the score bands for a signup strength bar so weak/medium/strong hints feel right.
- Security training — Demonstrate the crack-time gap between weak and strong passwords to raise team awareness.
- Review default credentials — Check whether a device or system's initial password is too simple and must be rotated.
- Compare strategies — See whether a long random string or a complex short password actually has higher entropy.
- Policy compliance — Paste a candidate password to confirm it meets your organization's length and complexity policy before setting it.
- Password manager audit — Export passwords from your manager and run them through the analyzer to identify weak entries that need rotation.
FAQ
How is the strength score computed?
Mainstream approaches estimate entropy from length, charset size, dictionary hits, and patterns like repeats or keyboard runs, then convert that to a crack time, rather than merely counting character classes.
Is the crack-time estimate reliable?
It is an order-of-magnitude reference based on an assumed guess rate. Real speed depends on attacker hardware and whether your password is stored with a salted slow hash. Treat it as relative, not a promise.
Which matters more, length or complexity?
Length usually pays off more. A 16-char random lowercase string often beats an 8-char "complex" password in entropy, so longer tends to be safer than fancier.
Why does P@ssw0rd score low?
Such symbol-for-letter substitutions are standard rules in attack dictionaries; cracking tools try them automatically, so they add little real strength.
Is the password I enter stored?
No. Analysis runs inside your browser, with no server upload and no logging. To be safe, test a structurally similar throwaway phrase rather than pasting your live primary password.
Any browser compatibility requirements?
This tool works in all modern browsers (Chrome, Firefox, Edge, Safari). No plugins or extensions required.
Can I use it offline?
After initial load, most features work offline. The core logic runs entirely in your browser with no network dependency.
Comments
Comments are stored locally in your browser. Configure Giscus for cloud-based comments.