Generate RFC 7636 PKCE code_verifier and S256 code_challenge pairs.
Execution runs 100% locally inside the browser sandbox using HTML5 Canvas, Web Cryptography Subtle API, and Web Workers. Zero egress.
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.
Click Regenerate Pair to generate a random 64-char verifier.
Send the S256 code_challenge to the OAuth authorization endpoint.
Exchange the code_verifier for access tokens at the token endpoint.
PKCE (Proof Key for Code Exchange) protects single-page and mobile apps from authorization code interception attacks without requiring client secrets.
S256 hashes the code_verifier with SHA-256 and encodes the digest using Base64URL.
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