Vigenère Cipher

A polyalphabetic substitution cipher.

About the Vigenère Cipher

The Vigenère cipher is a method of encrypting alphabetic text by using a simple form of polyalphabetic substitution. A keyword is used to shift the letters of the plaintext, with each letter of the keyword providing a different shift amount. This makes it more robust than a simple Caesar cipher. It's a classic example of a symmetric-key encryption system, and understanding it is a great step into the world of cryptography.

How to Use This Tool

  1. Enter Text: Type or paste the message you want to encrypt or decrypt.
  2. Enter Keyword: Provide a keyword. The keyword will be repeated to match the length of your message.
  3. Encrypt or Decrypt: Click the appropriate button to perform the cipher operation.
  4. View Result: The transformed message will appear in the "Result" box.