The rot-13 Page
Gur ebg-13 Cntr

The rot-13 Decoder

If your browser supports JavaScript, you can use this decoder to scramble and unscramble rot-13 text.


What is rot-13?

Rot-13 is a cipher commonly used in the Usenet newsgroups. It scrambles the text of a message so that it is not immediately readable. Rot-13 is often used as a courtesy, to avoid spoiling the ending of a movie or to hide an offensive joke. To read the scrambled message, the user must apply rot-13 again, which reveals the readable text. Most newsreader programs provide a way to apply rot-13.

The cipher is very simple: each character in the text is rotated 13 positions in the alphabet, cycling around at the end. Numbers and punctuation are not affected. To unscramble the text, reapply rot-13. Since there are 26 letters in the alphabet, performing rot-13 twice returns the text to its original state.

a -> n n -> a A -> N N -> A
b -> o o -> b B -> O O -> B
c -> p p -> c C -> P P -> C
d -> q q -> d D -> Q Q -> D
e -> r r -> e E -> R R -> E
f -> s s -> f F -> S S -> F
g -> t t -> g G -> T T -> G
h -> u u -> h H -> U U -> H
i -> v v -> i I -> V V -> I
j -> w w -> j J -> W W -> J
k -> x x -> k K -> X X -> K
l -> y y -> l L -> Y Y -> L
m -> z z -> m M -> Z Z -> M
Rot-13 Substitutions

Notable rot-13's

Rot-13 Word Pairs

Applying rot-13 to one word in the pair will produce the other.
abanon
abbanoon
AbeNor
abjurernowhere
ahnu
ahanun
AnaNan
anilnavy
antnag
ArvyNeil
balkonyx
bananaonanan
barone
BarnyOneal
barfones
beor
BecunaOrphan
binova
BSOF
ByranOlena
clerkpyrex
chapun
chatpung
ChechenPurpura
CherPure
CherylPurely
cragpent
craxpenk
crexperk
CubaPhon
cynarplane
ebbsroof
envyrail
ernerear
errsreef
ersref
FaberSnore
farosneb
flapsync
fubbyshoon
fubarshone
furshe
gagtnt
geltry
GenreTraer
GITV
GlareTyner
GleeTyrr
GlenTyra
gnattang
greenterra
GreenyTerral
gurlthey
hernurea
HEYURL
INKVAX
IraqVend
irkvex
IvanVina
JunesWharf
JungWhat
JuraWhen
jrwe
IQVD

Rot-13 Anagrams

Some rot-13's produce the same letters, but rearranged.
argentennetragna
baboononobba
boughtobhtug
gnattang
ravineenivar
tangantangangnatnagnatna

Generated Lists

Here is a Perl script to generate rot-13 word pairs and anagrams from word lists: rot13analyzer.pl.

The script reads one or more word lists that you provide and searches them for interesting rot-13's. Word-pair matches are written with a "W:" prefix, and anagram matches are written with an "A:" prefix.

I ran the script on two different word lists available on the Internet:

Challenge

If you discover any other rot-13 word pairs or anagrams, please let me know, and I will add them to the list.

Thanks to all who have contributed.


[HOME] - Darin Franklin | dfranklin@pobox.com