ROT13 Encoder

Quickly encode and decode text using ROT13 cipher.

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ROT13 is a simple letter substitution cipher that replaces a letter with the 13th letter after it in the alphabet. Because there are 26 letters in the alphabet, encoding and decoding use the same operation.

About this Tool

ROT13 ("rotate by 13 places") is a special case of the Caesar cipher with a shift of 13. Because the English alphabet has 26 letters, applying ROT13 twice returns the original text, making encoding and decoding the same operation. ROT13 is commonly used on internet forums to hide spoilers, punchlines, or potentially offensive content. It provides no security and is purely for obfuscation.

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