Shift letters by any amount to encrypt or decrypt a Caesar cipher. Live output, ROT13 included.
It shifts every letter a fixed number of places in the alphabet. A shift of 3 turns A into D, B into E, and so on. It's one of the oldest known ciphers.
ROT13 is just a Caesar cipher with a shift of 13. Because the alphabet has 26 letters, applying ROT13 twice returns the original text. Set the shift to 13 here to use it.
No. A Caesar cipher is trivially broken and is for learning, puzzles and CTFs only. For real protection use the AES tool.