root@generate-random:~/encryption-keys/ruby$ _

Generate Encryption Keys in Ruby - OpenSSL & SecureRandom

Complete code tutorial with examples and best practices

Ruby

[ Code Example - Quick Summary ]

Language: Ruby

What: Generate AES and RSA encryption keys in Ruby using OpenSSL and SecureRandom for secure encryption and decryption.

Try it: Use our interactive Encryption-keys generator or integrate this code into your Ruby application.

Generate AES and RSA encryption keys in Ruby using OpenSSL and SecureRandom for secure encryption and decryption. Looking for other languages? Check our code examples in PHP , JavaScript , Python , Java , C# , C++ and Go or use our interactive web generator.

Ruby Code Example

require 'openssl'
require 'securerandom'
require 'base64'

# AES-256 Key Generation
aes_256_key = SecureRandom.random_bytes(32) # 256 bits
aes_256_hex = aes_256_key.unpack1('H*')
aes_256_base64 = Base64.strict_encode64(aes_256_key)

puts "AES-256 Key (Hex): #{aes_256_hex}"
puts "AES-256 Key (Base64): #{aes_256_base64}"

# AES-128 Key
aes_128_key = SecureRandom.hex(16) # Returns hex string (16 bytes)
puts "AES-128 Key (Hex): #{aes_128_key}"

# RSA Key Pair Generation (2048-bit)
rsa_key = OpenSSL::PKey::RSA.new(2048)

private_key_pem = rsa_key.to_pem
public_key_pem = rsa_key.public_key.to_pem

puts "Private Key:\n#{private_key_pem}"
puts "Public Key:\n#{public_key_pem}"

# Export in DER format (binary)
private_key_der = rsa_key.to_der
public_key_der = rsa_key.public_key.to_der

private_key_base64 = Base64.strict_encode64(private_key_der)
puts "Private Key (Base64): #{private_key_base64}"

# Password-protected private key
encrypted_key = rsa_key.to_pem(OpenSSL::Cipher.new('AES-256-CBC'), 'password')
puts "Encrypted Private Key:\n#{encrypted_key}"

[EXPLANATION]

Ruby's SecureRandom module provides cryptographically secure random generation. Use SecureRandom.random_bytes(n) for raw bytes (32 for AES-256, 16 for AES-128) or SecureRandom.hex(n) for hexadecimal strings. unpack1('H*') converts bytes to hex. For RSA, OpenSSL::PKey::RSA.new(bits) generates a key pair with the specified bit length (2048 or 4096). to_pem exports keys in PEM format (ASCII), while to_der exports in DER format (binary). To password-protect private keys, pass a cipher and password to to_pem (e.g., OpenSSL::Cipher.new('AES-256-CBC')).

Expected Output

AES-256 Key (Hex): d2f5a8c1e4b7f3a9d6c2e5b8f1a4c7d2e9c3f6a8d1b4e7f2a5c8d1e4b7f3a9d6
AES-256 Key (Base64): 0vWoweS386nWwuW48aTs0unD9qjRtOfypsjR5Lfzqdbo=
AES-128 Key (Hex): f3a7d2e5c1b8f4a9d6c3e7b2f5a8c1d4
Private Key:
-----BEGIN RSA PRIVATE KEY-----
MIIEvgIBADANBgkqhkiG9w0BAQEFAASCBKgwggSkAgEAAoIBAQC9...
-----END RSA PRIVATE KEY-----
Public Key:
-----BEGIN PUBLIC KEY-----
MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAvd...
-----END PUBLIC KEY-----