Apply the ROT13 letter-substitution cipher. Because it shifts by 13, the same action both encodes and decodes.
Text • cipher
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ROT13 ("rotate by 13") is a simple substitution cipher that shifts each letter 13 places in the alphabet. Because the alphabet has 26 letters, applying ROT13 twice returns the original text — so the same action both encodes and decodes.
It is used to hide spoilers, puzzle answers and punch-lines in plain sight, not for real security. Type any text to scramble or unscramble it instantly, all in your browser.