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Frequently Asked Questions
What is ROT13?
ROT13 ("rotate by 13 places") is a simple letter substitution cipher that replaces each letter with the letter 13 positions after it in the alphabet. It's its own inverse - applying ROT13 twice returns the original text.
How does ROT13 work?
ROT13 shifts each letter 13 positions in the alphabet. Since there are 26 letters, shifting by 13 twice brings you back to the original letter. Only letters are affected - numbers, punctuation, and spaces remain unchanged.
Is ROT13 secure?
No, ROT13 provides no real security and is easily reversible by anyone. It's not an encryption method but rather an obfuscation technique historically used in online forums to hide spoilers or solutions.
Where is ROT13 used?
ROT13 was commonly used in early internet forums and Usenet newsgroups to obscure text content like spoilers, puzzle answers, or offensive material. It's essentially a "child-safe" filter for text.