Encoding and decoding
There is no separate direction: the same immediate conversion turns plain text into ROT13 text and turns ROT13 text back into plain text.
ROT13
Encode or decode text with the fixed 13-letter alphabet shift.
Codes
Enter a message: ROT13 replaces each letter with the one 13 positions later in the alphabet. Applying the same operation again recovers the original text.
ROT13 alphabet
AlphabetABCDEFGHIJKLMNOPQRSTUVWXYZ
ROT13NOPQRSTUVWXYZABCDEFGHIJKLM
Source text
Result
Quick explanation
Paste or type source text. The result updates immediately: A becomes N, B becomes O, and N becomes A again. Spaces, digits, and punctuation stay visible.
Try this too
Need another shift?
Use the Caesar cipher tool to freely choose a shift value from 1 to 25.
Additional information
Understanding ROT13
ROT13 means a rotation by 13 positions. It is a special Caesar cipher: each letter moves 13 places through the alphabet. Since the Latin alphabet has 26 letters, applying ROT13 a second time cancels the first shift.
What stays visible
Spaces, digits, and punctuation stay in place to preserve the message structure. Accented letters are reduced to their base letters so the tool works on A-Z.
Common use
ROT13 is mainly used to lightly hide an answer, hint, or solution. It is not strong encryption, but it is convenient in puzzles and forums.
ROT13 correspondence table
| Plain alphabet | A | B | C | D | E | F | G | H | I | J | K | L | M |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| ROT13 | N | O | P | Q | R | S | T | U | V | W | X | Y | Z |
| Plain alphabet | N | O | P | Q | R | S | T | U | V | W | X | Y | Z |
| ROT13 | A | B | C | D | E | F | G | H | I | J | K | L | M |
Quick example
SECRET becomes FRPERG. Applying ROT13 to FRPERG gives SECRET back.
Related tools
To choose an exact shift, use the Caesar cipher. To test every shift, use the automatic Caesar decoder. For a changing key, try Keyword shift or the Vigenère cipher.
Learn more
See also the Wikipedia article about ROT13.
Limits and reuse
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