Password Entropy & Strength Analyzer
Calculate mathematical Shannon entropy in bits, crack-time estimations, character space analysis, and NIST SP 800-63B compliance locally in your browser.
1 How to Use Password Entropy & Strength Analyzer
- 1. Type any password or passphrase.
- 2. View instant entropy score in bits, pool size, and crack time.
- 3. Inspect NIST compliance checklist.
⚙️ Cryptographic Specifications
- Algorithm
- NIST Entropy
- Execution Engine
- Web Cryptography API (SubtleCrypto)
- Environment
- Client Browser Sandbox
- Network Telemetry
- 0 Bytes (Zero Server Transmission)
🛡️ Security & Compliance
Enterprise developers can safely execute this tool with production secrets. Because execution takes place entirely within your browser's local V8 JavaScript runtime, no payloads are transmitted over HTTP, cached on third-party proxies, or stored in server logs.
Verified Safe for SOC2, HIPAA, and GDPR developer compliance audits.
Frequently Asked Questions
What is a strong entropy score?
Above 60 bits is generally resistant to offline dictionary attacks; above 80 bits is considered cryptographically strong.
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