Security

Generate, validate and verify OAuth2 / OIDC PKCE (RFC 7636) code_verifier and S256 code_challenge pairs. Three modes: (1) generate a fresh verifier + challenge from cryptographically secure random bytes at 256/384/512/768-bit entropy, (2) audit a verifier you already have against the RFC — length (43–128), charset [A-Za-z0-9-._~] and ≥256-bit entropy, and (3) verify a verifier/challenge pair by recomputing BASE64URL(SHA256(verifier)). Optionally build the full authorization-request URL and token-exchange body. Complements the generic nonce-generator (which only emits a verifier+challenge pair) with RFC-compliance auditing and pair verification.

Validation

Validate and format phone numbers internationally

Cryptography

Audit ML-DSA / SLH-DSA / FN-DSA / BBS+ / PLONK / Halo2 parameter compatibility, proof sizes and trusted-setup requirements, with a live pure-TS ML-DSA (FIPS 204) demo

Security

Generate ML-KEM-512/768/1024 (FIPS 203 / CRYSTALS-Kyber) keypairs, encapsulate a random shared secret against the public key, decapsulate it with the private key, and verify both sides match — with the exact wire sizes of all three parameter sets checked live against the standard.

Security

Generate cryptographically secure one-time tokens for web security scenarios — CSRF tokens, OAuth/OIDC state parameters, session nonces, and PKCE code_verifier/code_challenge (S256). Uses crypto.randomBytes, never Math.random.

Validation

Validate or generate numbers using the Modulus-11 (ISO 7064) check-digit algorithm with ISBN-10 (10..2), Norwegian-ID (3,7,6,1,8,9,4,5,2) and generic 2-7 weight schemes.

Security

Generate or validate 12 to 24 word BIP39 mnemonic phrases with entropy and PBKDF2-HMAC-SHA512 seed output

Validation

Validate or generate numbers using the Luhn algorithm (mod-10). Works for credit cards, IMEI, IMEISV, SIN, NPI and any custom Luhn-based identifier.

Validation

Validate MAC addresses and identify vendor information

Security

Generate JSON Web Keys (JWK) for RSA, EC (P-256/P-384/P-521/secp256k1), and OKP (Ed25519/Ed448/X25519/X448), or parse an existing JWK to inspect its parameters, thumbprint, and metadata

Security

Decode a JWT (header + payload) with syntax highlighting, diagnose standard claims, and verify the signature with HS*/RS*/PS*/ES*/EdDSA keys — plus a tampered-token forgery demo

Security

Decode JWT header and payload, verify HS256 or RS256 signatures, and flag algorithm, expiry, and sensitive-claim security risks