Verify HS256 signed JSON Web Tokens against secret keys with zero network egress.
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.
Enter or configure parameter fields in the workspace.
All calculations execute client-side with zero network egress.
Copy output or download generated assets directly.
Yes, 100% free and processes data locally in your browser.
Explore related utilities in the Security & Network suite
Compare memory hardness, GPU ASIC resistance, and security parameters across KDF standards.
Generate secure RFC 6238 Base32 TOTP secret keys and standard otpauth:// URIs for Google Authenticator.
Generate RFC 6844 CAA iodef DNS records to receive unauthorized TLS issuance alerts.
Compute 512-bit NIST FIPS 202 SHA-3 cryptographic hashes in-browser.
