Real-time strength analysis, entropy measurement, & database reuse prevention DEV </> BY ANTONYKUMAR
Enter a password below to evaluate its complexity, bits of entropy, and leaks against compromised credentials in real-time.
Create high-entropy passwords or memorable Diceware passphrases instantly.
Simulates enterprise systems preventing the reuse of old passwords. Passwords are hashed locally using the cryptographically secure SHA-256 algorithm.
Entropy measures the level of randomness or unpredictability in a password. In cybersecurity, we use bits of entropy to determine the difficulty of guessing a password via brute-force.
Where:
Complexity vs Length: Adding just 2 characters to a password's length ($L$) increases security exponentially faster than introducing symbols or numbers to a short password. A long, simple phrase (e.g. correct-horse-battery-staple, Diceware) has significantly higher entropy and is much easier to remember than a short, complex password like Tr0$v!.
Modern servers never store passwords in clear text. Instead, passwords undergo a one-way mathematical function called hashing.
How do websites check if your password was leaked in a data breach without knowing what your password is? They use a cryptographic privacy model called k-Anonymity.
Services like Have I Been Pwned implement this secure lookup:
21BD1) to the server.