OpenSSL Secure Generation

Generate cryptographically secure random data using openssl rand.

Password/Secret Generation

# 32 random bytes as base64 (43 chars, URL-safe with tr)
openssl rand -base64 32 | tr '+/' '-_' | tr -d '='

# 24 random bytes as hex (48 chars)
openssl rand -hex 24

# alphanumeric password (32 chars)
openssl rand -base64 48 | tr -dc 'a-zA-Z0-9' | head -c 32

Common Lengths

Use Case

Command

Password (strong)	openssl rand -base64 24
API key	openssl rand -hex 32
Session token	openssl rand -base64 48
Short PIN (8 digits)	openssl rand -hex 4 | xxd -r -p | od -An -tu4 | tr -d ' ' | head -c 8

Notes

• -base64 outputs ~1.33x the byte count in characters
• -hex outputs 2x the byte count in characters
• Pipe through tr -dc to filter character sets
• Always use at least 16 bytes (128 bits) for secrets