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ROT13 Encoder/Decoder
ROT13 is a simple letter substitution cipher that replaces each letter with the 13th letter after it in the alphabet. Encoding and decoding are the same operation.
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How ROT13 Works
Each letter is shifted 13 positions in the alphabet:
A B C D E F G H I J K L M
N O P Q R S T U V W X Y Z
Examples
- Hello becomes Uryyb
- Secret becomes Frperg
- ABC becomes NOP
- ROT13 becomes EBG13
About ROT13
ROT13 is a special case of the Caesar cipher, developed in ancient Rome. Because the alphabet has 26 letters and 13 is half of 26, applying ROT13 twice returns the original text.
Note: ROT13 is not secure encryption - it is meant for obscuring text (like hiding spoilers) rather than protecting sensitive information.