RSA Express Encryption/Decryption Calculator

This worksheet is provided for message encryption/decryption with the RSA Public Key scheme. No provisions are made for high precision arithmetic, nor have the algorithms been encoded for efficiency when dealing with large numbers.

To use this worksheet, you must supply:

• a modulus N, and either:
  • a plaintext message M and encryption key e, OR
  • a ciphertext message C and decryption key d.

The values of N, e, and d must satisfy certain properties. See RSA Calculator for help in selecting appropriate values of N, e, and d.

The largest integer your browser can represent exactly is

To encrypt a message, enter valid modulus N below. Enter encryption key e and plaintext message M in the table on the left, then click the Encrypt button. The encrypted message appears in the lower box.

To decrypt a message, enter valid modulus N below. Enter decryption key d and encrypted message C in the table on the right, then click the Decrypt button. The decrypted message appears in the lower box.