crypto

Cryptographic hash functions, HMAC, and random bytes via OpenSSL (libcrypto). All hash/HMAC functions return hex-encoded strings.

crypto.sha256(input)

Compute SHA-256 hash of a string.

const hash = crypto.sha256("hello");
// "2cf24dba5fb0a30e26e83b2ac5b9e29e1b161e5c1fa7425e73043362938b9824"

crypto.sha512(input)

Compute SHA-512 hash of a string.

const hash = crypto.sha512("hello");

crypto.md5(input)

Compute MD5 hash of a string.

const hash = crypto.md5("hello");
// "5d41402abc4b2a76b9719d911017c592"

crypto.hmacSha256(key, data)

Compute HMAC-SHA256 of data using key. Returns a 64-character lowercase hex string. Use this for webhook signature verification and JWT signing.

const sig = crypto.hmacSha256("secret", "payload");
// "f7bc83f430538424b13298e6aa6fb143ef4d59a14946175997479dbc2d1a3cd8"

crypto.pbkdf2(password, salt, iterations, keylen)

Derive a key using PBKDF2-HMAC-SHA256. Returns a hex string of keylen bytes (2×keylen characters). Use for password hashing and key derivation.

const hash = crypto.pbkdf2("password", "salt", 1, 20);
// "0c60c80f961f0e71f3a9b524af6012062fe037a6"

const key = crypto.pbkdf2(userPassword, randomSalt, 100000, 32);

crypto.randomBytes(n)

Generate n random bytes, returned as a hex string (2n characters).

const token = crypto.randomBytes(16);
// 32-character random hex string, e.g. "a1b2c3d4e5f6..."

crypto.randomUUID()

Generate a v4 UUID string.

const id = crypto.randomUUID();
// "550e8400-e29b-41d4-a716-446655440000"

Example

const password = "secret123";
const hash = crypto.sha256(password);
console.log(hash);

const sessionId = crypto.randomBytes(32);
console.log(sessionId);

const uuid = crypto.randomUUID();
console.log(uuid);

Native Implementation

API	Maps to
crypto.sha256()	OpenSSL EVP API (EVP_sha256)
crypto.sha512()	OpenSSL EVP API (EVP_sha512)
crypto.md5()	OpenSSL EVP API (EVP_md5)
crypto.hmacSha256()	OpenSSL HMAC() with EVP_sha256
crypto.pbkdf2()	OpenSSL PKCS5_PBKDF2_HMAC() with EVP_sha256
crypto.randomBytes()	RAND_bytes()
crypto.randomUUID()	RAND_bytes(16) + version/variant bits + snprintf