Security

Show each HMAC step of HKDF Extract+Expand for protocol key derivation, including PRK, T(n), and OKM.

Security

Generate cryptographically secure random key material driven by entropy budget — request N bits of entropy, get hex/base64/base64url output. Also supports custom-alphabet strings via crypto.randomInt (rejection-sampled, no modulo bias). Use this instead of Math.random()-based tools for any secret/key/token.

Security

Audit HTTP response headers for security compliance — parses the raw headers you paste (no network) and grades them against the OWASP secure-header set with value-level checks: HSTS max-age, CSP unsafe-inline/eval, X-Content-Type-Options, Referrer-Policy, Permissions-Policy, COOP/COEP/CORP and more. Outputs a letter grade (A+ to F) plus per-header findings with copy-ready fix recommendations.

Security

Split a secret into n shares where any k (the threshold) are required to reconstruct it — Shamir's k-of-n scheme over GF(256). Pure in-process cryptography (crypto.randomBytes for polynomial coefficients), no network. Split a password/key/passphrase into shares held by separate people, then combine any k of them to recover it. Confidentiality only — no authenticity.

Security

Encrypt text with an RSA public key or decrypt ciphertext with the matching private key, using OAEP padding (SHA-1 or SHA-256). Handles long messages by chunking. Keys and data stay local. PKCS#1 v1.5 is intentionally not offered (Node disables it for decryption due to Bleichenbacher attacks).

Security

Generate an RSA key pair (2048/3072/4096-bit) as PEM-encoded public and private keys. Optionally encrypt the private key with a passphrase. PKCS#8 (recommended) or PKCS#1 private key format. Everything runs locally.

Security

Generate an SSH key pair (Ed25519 recommended, RSA 4096, or ECDSA P-256) with an OpenSSH-format public key ready for ~/.ssh/authorized_keys, a SHA256 fingerprint, and a PEM private key. Optional passphrase encryption. Runs locally.

Validation

Validate 9-digit US ABA bank routing numbers (RTN) with MICR check-digit verification, Federal Reserve district lookup and ABA institution breakdown.

Validation

Validate 7-character UK/Irish SEDOL securities identifiers with weighted mod-10 check-digit verification and SEDOL-7 structure breakdown.

Validation

Lint robots.txt syntax, flag risky rules, and test important URLs before you ship crawler directives

Validation

Simulate the reading order and spoken semantics a screen reader may expose from a URL or raw HTML, then flag likely accessibility gaps

Security

Detect common SQL injection attack patterns in input strings