🔐 ROT13 & Caesar Cipher
Encode or decode with ROT13 or any Caesar shift. Brute-force view cracks unknown shifts.
About this tool
The Caesar cipher shifts each letter by a fixed number of positions; ROT13 is the special case of a shift of 13 (which is its own inverse). Type your message, pick a shift, and see the result instantly. To decode a message when you don't know the shift, expand the brute-force panel — it shows all 25 possible shifts so you can spot the readable one.
Letters keep their case; numbers, spaces and punctuation pass through unchanged. Everything runs locally — note that these are classical ciphers for fun and learning, not secure encryption.
🔓 Brute force — all 25 shifts
Click any row to load that shift into the converter.