NIST Password Entropy & Brute-Force Time Estimator
Calculate Shannon bits of entropy and estimate GPU cluster cracking times.
Execution runs 100% locally inside the browser sandbox using HTML5 Canvas, Web Cryptography Subtle API, and Web Workers. No data is ever transmitted across the network.
Zero network latency. Operates completely offline with zero dependencies on third-party backend servers or cloud services.
Built according to official RFC specifications, cryptographic test vectors, and enterprise-grade data transformation standards.
How to Use NIST Password Entropy & Brute-Force Time Estimator
Enter your password to audit its cryptographic entropy.
Review total pool size, Shannon bits score, and strength classification.
View estimated time required to crack the password under GPU and supercomputer attacks.
Frequently Asked Questions
How many bits of entropy is considered secure?
NIST and security standards consider 60+ bits strong and 80+ bits virtually unbreakable against modern brute-force attacks.
Does this tool upload my password to any server?
No, the calculation is performed 100% locally in your browser memory via pure client-side math.
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