Overview
The Caesar Cipher tool encrypts and decrypts text using the classic substitution cipher where each letter is shifted a fixed number of positions in the alphabet. In decrypt mode, it can perform a brute-force attack, displaying all 25 possible shifts simultaneously.
How to Use
Type your message in the input field and adjust the rotation slider from 1 to 25 (ROT13 at position 13). Switch between Encrypt and Decrypt modes. In Decrypt mode, activate “Show All Shifts” to see all 25 possible decryptions at once — useful when you don’t know the original shift value. An alphabet visualization shows the current mapping.
Background & Context
The Caesar cipher is named after Julius Caesar, who reportedly used it with a shift of 3 to communicate with his generals. Despite being easily broken today, it was effective in its time when literacy was rare. ROT13 (shift of 13) is a special case because applying it twice returns the original text. It was widely used on early internet forums to hide spoilers.
