Caesar Cipher
A classic substitution cipher that shifts letters along the alphabet.
Usage
What is the Caesar Cipher
The Caesar Cipher is the simplest and best-known substitution cipher. Each letter in the plaintext is shifted by a fixed number of positions along the alphabet to produce the ciphertext. For example, with a shift of 3, A becomes D and B becomes E.
Steps
1. Set the shift (0-25); 2. Enter text in the input box; 3. Click "Encrypt" to convert plaintext to ciphertext; 4. Click "Decrypt" to restore ciphertext to plaintext (the same shift is required).
Notes
Only English letters (a-z, A-Z) are processed; non-letter characters remain unchanged. The cipher is extremely insecure and is intended for educational purposes only. Decryption requires the same shift used for encryption, otherwise the original text cannot be restored.