ROT13 decoder and encoder
Type or paste text. The same step encodes and decodes.
Paste the result back in and you get your original text: the same step encodes and decodes.
Full chart
- AN
- BO
- CP
- DQ
- ER
- FS
- GT
- HU
- IV
- JW
- KX
- LY
- MZ
- NA
- OB
- PC
- QD
- RE
- SF
- TG
- UH
- VI
- WJ
- XK
- YL
- ZM
How ROT13 works
ROT13 moves every letter 13 places along the alphabet. Because the alphabet has 26 letters, that is exactly half of it: A becomes N, B becomes O, and so on to M, which becomes Z, and the second half maps back.
That is why one step does both jobs. Apply ROT13 to a message and you get the code; apply it again and you get the message back. Numbers, spaces and punctuation stay as they are, and capital and small letters stay as typed.
Example: HELLO
Replace each letter with the one 13 places away:
- HU
- ER
- LY
- LY
- OB
Result: URYYB
Other ciphers
The Atbash cipher reverses the alphabet instead of shifting it. Letters can also become numbers with A1Z26 or pairs of digits with the Polybius square. All of them are on the scout codes page.