Password Strength Checker
Analyze password strength with entropy scoring, crack time estimate, and warnings. Free online checker, no upload, browser-based.
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Frequently asked questions
- How is strength calculated?
- Measures character variety (lower, upper, digits, symbols), length, and estimates entropy. Also flags common passwords and patterns.
- Safe to type my password?
- Yes. Analysis runs entirely in your browser. Nothing is sent over network. You can verify by disconnecting internet and reloading.
- What does crack time mean?
- A rough estimate assuming an offline attacker testing 10 billion passwords per second against a fast hash.
- What exactly does it check?
- Length, whether lowercase, uppercase, digits, and symbols are present, and then patterns: a short list of very common passwords, repeated characters, and sequential runs. Each warning lowers the score.
- Is this as thorough as zxcvbn?
- No. It is a character-class and entropy heuristic with a small common-password list, so it misses dictionary words, keyboard walks, and dates that a dedicated estimator would catch. Treat a good score as a floor, not a guarantee.