RSA Encrypt/Decrypt Online - EXUtil Extended Utilities

Free online RSA asymmetric encryption and decryption tool. Generate RSA key pairs (1024/2048/4096-bit) and perform public key encryption, private key decryption.

How to use

  1. Paste or import the content you want to process.
  2. Choose an available action and run the tool.
  3. Review the result, then copy or download the output.

Frequently asked questions

RSA key sizes?
1024 (insecure), 2048 (recommended), 4096 (highest security).
Public vs private key?
Public: encrypt/verify, can share. Private: decrypt/sign, must keep secret.
RSA data length limit?
~1/8 of key length (256 bytes for 2048-bit). Use hybrid encryption (RSA+AES) for large data.
RSA too slow?
Use RSA to encrypt AES key, AES for actual data. Best of both worlds.
How to store private key?
HSM, key management systems, or encrypted files. Never hardcode in production.