How to Use
- After the page loads, disconnect your device from the network if you want extra peace of mind.
- Click "Load Weak Example" or "Load Strong Example" to see how the score changes.
- Type the password you want to evaluate, or use a similar pattern instead of the exact real password.
- Review crack time, score bar, warnings, and suggestions.
- Improve length, randomness, or phrase structure based on the feedback.
Core Features
- zxcvbn-based scoring: The tool checks more than length, including common words, keyboard patterns, repetition, and dates.
- Works after the page loads: The algorithm and dictionaries run in the front end, so you can disconnect before testing a sample password.
- Readable crack time: See an offline slow-hashing crack time estimate with a clear risk score bar.
- Real-time weakness feedback: Warnings and suggestions update as you type so you can improve the password structure.
- Safer examples included: Load weak and strong sample passwords before deciding whether to test a same-pattern substitute.
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Calculation Logic
This tool uses Dropbox's open-source zxcvbn password strength estimator. It estimates how many guesses an attacker would need, then translates that into a readable crack time for an offline slow-hashing attack scenario.
The check runs in the browser and does not send input to a backend. As a good security habit, prefer testing a same-pattern substitute instead of your exact real password.
FAQ
Is it safe to type my real password?
The tool does not upload your input, but the safer habit is to test a same-pattern substitute rather than the exact real password, especially on shared devices.
How is crack time calculated?
zxcvbn estimates guesses from dictionaries, keyboard patterns, repetition, dates, and composition, then converts the guesses into time.
Why can a long password still be weak?
If it is built from common phrases, sequences, or known patterns, attackers may guess those patterns early, reducing the benefit of length.
Does it work offline?
After the page loads, the evaluation logic runs locally in the browser, so you can disconnect and keep testing.
Does a high score mean the password cannot be cracked?
No. A high score means the pattern is harder to guess and more expensive to attack. It does not guarantee permanent safety or replace a password manager and two-factor authentication.