RSA Encryption Tool
Encrypt text using RSA public key encryption with key sizes up to 4096 bits. Free online RSA encryption with key pair generation.
Configuration
Input (Plaintext)
What is RSA Encryption?
RSA (Rivest-Shamir-Adleman) is a public-key cryptosystem widely used for secure data transmission. It uses two keys: a public key for encryption and a private key for decryption. RSA security relies on the difficulty of factoring large prime numbers.
How to Use RSA Encryption
When to Use RSA Encryption
How RSA Encryption Works
RSA encryption uses modular exponentiation with a public key (n, e) to transform plaintext into ciphertext. The message is converted to a number and raised to the power e, then taken modulo n. Only the corresponding private key can decrypt the message.
Common Use Cases
- Secure email (PGP/GPG)
- Digital signatures
- SSL/TLS certificates
- Secure key exchange
- Authentication systems
- Blockchain and cryptocurrencies
FAQs
1 What key size should I use?
2048 bits is the current standard for most applications. Use 4096 bits for higher security requirements, though it is slower.
2 Can I encrypt large files with RSA?
RSA is typically used to encrypt small amounts of data or symmetric keys. For large files, use hybrid encryption: encrypt the file with AES, then encrypt the AES key with RSA.
3 Is RSA quantum-safe?
No, RSA will be vulnerable to quantum computers. NIST is developing post-quantum cryptography standards.