Skip to main content
What it is:
RSA encryption is typically “public key encrypts → private key decrypts”. Core idea:
  • If I have your public key, I can encrypt a message for you
  • Only you (with the private key) can decrypt it
Practical note (why RSA isn’t used for everything):
RSA is not efficient for large data. It’s commonly used to encrypt small pieces of data like symmetric keys, not entire files. Try it (demo):
  1. Copy the public key from key generation
  2. Enter a short message (example: “Meet me at 5PM”)
  3. Encrypt using the public key
  4. You get ciphertext
Link: https://diveshfx.github.io/online-tools/rsa/encrypt/ or https://tiny.cc/rsaencrypt