Password Strength Checker
Check password strength, calculate entropy, estimate crack time. Free client-side password analyzer.
Frequently Asked Questions
What is password strength?
Password strength measures how resistant a password is to guessing and brute-force attacks. It depends on length, character variety, and randomness.
What is password entropy?
Entropy measures unpredictability in bits. Each bit doubles the required guesses. 80+ bits is considered very strong for offline attacks.
How is crack time estimated?
Crack time is estimated based on the password's entropy and assumed attacker capabilities (offline: billions of guesses/sec, online: ~1000 guesses/sec).
What makes a password weak?
Short length, common patterns, dictionary words, personal information, and character repetition all reduce password strength significantly.
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