ROT13 Decoder

ROT13 ("rotate by 13 places") is a simple letter substitution cipher that replaces a letter with the 13th letter after it in the alphabet.

It's a special case of the Caesar cipher and is its own inverse - the same algorithm is used for both encoding and decoding.

Example: "HELLO" becomes "URYYB" and "URYYB" becomes "HELLO" when decoded.