OpenSSL

Random Hex Is Not a Hash: Generating Cryptographic Random Values on Linux

A command such as openssl rand -hex 32 is often described as generating a “random hash.” The output certainly looks like a SHA-256 digest: 64 hexadecimal characters. But no hash operation has happened. OpenSSL generated 32 random bytes and encoded them as hexadecimal. That distinction matters. A hash function transforms input into a fixed-size digest. A cryptographically secure random number generator produces unpredictable bytes. If the requirement is a token, session secret, API credential, nonce, or other fresh random value, the random bytes are the important part. Hashing them afterward usually adds no useful unpredictability.