ROT13 Cipher
Encode text with ROT13, ROT5, ROT18, or ROT47
About
Apply the ROT13 cipher (or any Caesar shift from 1 to 25) to text. ROT13 is its own inverse, so the same operation encodes and decodes. Letter case is preserved and non-letters are left untouched. Everything runs in your browser; nothing is uploaded.
Related guides
Caesar Ciphers, ROT13, and Why Neither Is Encryption
What a shift cipher is, why ROT13 is self-inverse and useful for light obfuscation, and how frequency analysis breaks even large keys efficiently.
Letter Frequency Analysis: How Frequency Stats Crack Substitution Ciphers
What the letter distribution in English looks like, how to use it to break a Caesar cipher, and what word and line stats reveal that individual letters miss.
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