Tiny Toolkit

ROT13 Encoder / Decoder

Encode or decode text using the ROT13 cipher, which rotates each letter 13 positions through the alphabet. ROT13 is self-inverse — applying it once encodes, applying it again decodes — so there is no separate encode/decode switch needed. Historically used on Usenet to hide spoilers and puzzle answers; still handy for casual obfuscation today.

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Frequently Asked Questions

What is ROT13?
ROT13 is a simple letter-substitution cipher that rotates each letter 13 positions through the alphabet. It was widely used on Usenet to obscure spoilers and puzzle answers.
Is ROT13 a form of encryption?
No. ROT13 provides no real security — anyone can decode it instantly. It is used purely for casual obfuscation, not data protection.
Do I need a separate decode step?
No — ROT13 is self-inverse. Applying it twice returns the original text, so the same tool both encodes and decodes.

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