Password Strength Validator
Check password strength — entropy estimate, character classes, and common patterns.
Runs locally in your browser. Your input is not uploaded.
How to Use
- 1
Type candidate passwords
One per line — analysis is local-only.
- 2
Read strength and flags
Entropy estimate plus missing classes and risky patterns.
- 3
Prefer long passphrases
Aim for 80+ bits — length beats symbol tricks.
Frequently Asked Questions
- By entropy: length × log2 of the character pool implied by the classes used (lowercase 26, digits 10, symbols 33…). Under 35 bits is very weak; 80+ is strong. Pattern penalties flag sequences, repeats, and dictionary hits separately.
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