JWT & HMAC Secret Key Generator
Generate cryptographic 256/384/512-bit signing secrets via Web Crypto CSPRNG.
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 JWT & HMAC Secret Key Generator
Choose 256-bit (32B), 384-bit (48B), or 512-bit (64B).
Click regenerate to sample fresh CSPRNG entropy.
Copy Base64URL or Hex secret for your .env configuration.
Frequently Asked Questions
How are the secrets generated?
Keys are generated in local browser RAM using window.crypto.getRandomValues() CSPRNG.
What is the recommended bit length for JWT?
OWASP recommends a minimum of 256-bit (32 bytes) for HS256 and 512-bit (64 bytes) for HS512.
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