Caesar Cipher

Encode and decode messages with a simple letter shift

Input (Plain Text or Cipher)

Output

What is a Caesar Cipher?

The Caesar cipher is one of the earliest and simplest forms of encryption. It's a substitution cipher where each letter in the plaintext is "shifted" a certain number of places down the alphabet. For example, with a shift of 3, 'A' would become 'D', 'B' would become 'E', and so on.

How to Use the Tool:

  • 1. Set the Shift Value: Use the slider at the top to select how many letters you want to shift your text by (from 1 to 25).
  • 2. Enter Your Text: Type or paste any text into the "Input" box on the left.
  • 3. View the Results: The "Output" box on the right will instantly show you both the encoded (encrypted) and decoded (decrypted) versions of your text based on the selected shift value.

Fun and Educational

While named after Julius Caesar, who used it for his private military correspondence, the Caesar cipher is not secure for modern communication. However, it's a fantastic tool for learning the basic principles of cryptography and encryption. Use it to send fun, secret messages to friends or to understand how simple letter substitution works!