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ROT47 Cipher

ROT47 encoder/decoder - rotates all printable ASCII characters by 47 positions. Self-reciprocal like ROT13.

ROT47 is self-reciprocal: encode and decode are the same operation. Enter either plaintext or ciphertext below.

Applies ROT47 to all printable ASCII characters (!"#$%...xyz{|}~)

How ROT47 Works

  • • Uses ASCII codes 33 (!) through 126 (~) — 94 characters
  • • Rotates each character by 47 positions (half of 94)
  • • Numbers, punctuation, and letters all get rotated
  • • Space (ASCII 32) is preserved unchanged
  • • Apply twice to get back the original text

Character Mapping

!
P
"
Q
#
R
$
S
%
T
&
U
'
V
(
W
)
X
*
Y
+
Z
,
[
-
\
.
]
/
^
0
_
1
`
2
a
3
b
4
c
5
d
6
e
7
f
8
g
9
h
:
i
;
j
<
k
=
l
>
m
?
n
@
o
A
p
B
q
C
r
D
s
E
t
F
u
G
v
H
w
I
x
J
y
K
z
L
{
M
|
N
}
O
~

ROT47 vs ROT13

FeatureROT13ROT47
CharactersA-Z, a-z (52)!-~ (94)
NumbersUnchangedRotated
PunctuationUnchangedRotated
Self-reciprocalYesYes

Puzzle Tips

  • • If ROT13 doesn't work but text has weird punctuation, try ROT47
  • • Look for strings where letters AND numbers both look scrambled
  • • Common in technical/programming puzzles
  • • Example: "Hello123" → "w6==@`ab"

What is ROT47?

ROT47 is a variant of the ROT13 cipher that operates on all 94 printable ASCII characters (from ! to ~) instead of just letters. Like ROT13, it's self-reciprocal—applying it twice returns the original text.

How It Works

The Algorithm

  1. Take each character's ASCII code (33-126)
  2. Subtract 33 to get a value 0-93
  3. Add 47 and take modulo 94
  4. Add 33 to get the new ASCII code

Why 47?

There are 94 printable ASCII characters. Half of 94 is 47, making the cipher self-reciprocal. Each character maps to its "opposite" in the range.

Examples

  • "Hello" → "w6==@"
  • "12345" → "`abcd"
  • "ROT47" → "#~%cf"
  • "!@#$%" → "POnml"

ROT47 vs ROT13

ROT13ROT47
Letters only (52 chars)All printable ASCII (94 chars)
Numbers unchangedNumbers rotated
Punctuation unchangedPunctuation rotated

In Puzzles

ROT47 appears when puzzle creators want to obscure:

  • URLs: Web addresses with symbols
  • Codes: Alphanumeric strings
  • Coordinates: Numbers and degree symbols
  • Programming: Code snippets or API keys

Recognition

Look for ROT47 when:

  • Text has unusual character combinations
  • Numbers appear where letters should be (or vice versa)
  • ROT13 doesn't produce readable output
  • The puzzle involves ASCII or computer themes