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Type the text to encode/decode.
Each letter shifts by 13 positions.
Copy the encoded text.
ROT13 is a simple letter substitution cipher that replaces each letter with the letter 13 positions after it in the alphabet. Since the English alphabet has 26 letters, applying ROT13 twice returns the original text, making it its own inverse. It has been widely used on the internet since the early Usenet days to hide spoilers and puzzle answers.
No, ROT13 provides absolutely no cryptographic security and should never be used to protect sensitive data. It is a trivial cipher that anyone can decode instantly without any key. Its purpose is purely for casual obfuscation, such as hiding spoilers, punchlines, or puzzle solutions where the intent is to prevent accidental reading.
No, ROT13 only transforms alphabetic characters (A-Z and a-z). Numbers, punctuation, spaces, and all other symbols remain completely unchanged. The cipher preserves the case of each letter, so uppercase letters stay uppercase and lowercase stay lowercase after transformation.
