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Sample texts…
Hello World
The Quick Brown Fox
Cryptography is Fun
Caesar Cipher 101
✕ Clear
Hello World
11 chars
Character Groups
✓ ␣ Space +1
✓ A–Z 26
a–z 26
0–9 10
Switch to CUSTOM base to toggle groups
Case Handling
Case Sensitive
A ≠ a
Lowercase
A → a = 26
UPPERCASE
a → A = 26
Extra Characters
,
.
?
!
:
;
'
"
-
/
Appended after group chars · duplicates ignored
BASE 27
BASE 26
ASCII
UNICODE
CUSTOM
BASE 27
Cipher Operation
1 KEY OPERATIONS
Addition
N(D) = N(o) + X mod T
Subtraction
N(D) = N(o) − X mod T
Multiply
N(D) = N(o) × X mod T
Division
N(D) = N(o) × X⁻¹ mod
2 KEY OPERATIONS
Scale (X+Y)
N(D) = N(o) × (X+Y) mo
Affine (×X+Y)
N(D) = N(o) × X + Y mo
Scale (X·Y)
N(D) = N(o) × (X·Y) mo
Formula
N(D) = N(o) × (13+6) mod 27 [= N(o) × 19 mod 27]
N(o) = N(D) × (13+6)⁻¹=10 mod 27
Key X
0 – 26
13
gcd(X,T) = 1 ✓
Key Y
0 – 26
6
Alphabet Map — 27 chars (T = 27)
␣
0
A
1
B
2
C
3
D
4
E
5
F
6
G
7
H
8
I
9
J
10
K
11
L
12
M
13
N
14
O
15
P
16
Q
17
R
18
S
19
T
20
U
21
V
22
W
23
X
24
Y
25
Z
26
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