Encode and decode text using ROT13 cipher with our free online tool. ROT13 replaces each letter with the letter 13 positions after it in the alphabet. Applying ROT13 twice returns the original text.
ROT13 is a simple letter substitution cipher that shifts each letter by 13 places. Since there are 26 letters in the English alphabet, applying ROT13 twice recovers the original text, making it its own inverse.