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Sample Encodings

Over time, some encoding schemes have been used so frequently that they've formed a kind of basic vocabulary for puzzlers. Here are some things to look out for as you try to determine how to extract a final answer.

Pictoral encodings

To view an image that contains every letter for a particular encoding, click the heading for that encoding.
Learn more about Morse Code
Learn more about Semaphore
Learn more about Braille
Learn more about Maritime flags
Learn more about American Sign Language

Textual Encodings

Letter A to Z
index
NATO
Phonetic
Alphabet
Binary
(base 2)
Ternary
(base 3)
ASCII
uppercase
(hexidecimal)
ASCII
lowercase
(hexidecimal)
Letter A to Z
index
NATO
Phonetic
Alphabet
Binary
(base 2)
Ternary
(base 3)
ASCII
uppercase
(hexidecimal)
ASCII
lowercase
(hexidecimal)
A 1 Alfa 00001 001 0x41 0x61 N 14 November 01110 112 0x4E 0x6E
B 2 Bravo 00010 002 0x42 0x62 O 15 Oscar 01111 120 0x4F 0x6F
C 3 Charlie 00011 010 0x43 0x63 P 16 Papa 10000 121 0x50 0x70
D 4 Delta 00100 011 0x44 0x64 Q 17 Quebec 10001 122 0x51 0x71
E 5 Echo 00101 012 0x45 0x65 R 18 Romeo 10010 200 0x52 0x72
F 6 Foxtrot 00110 020 0x46 0x66 S 19 Sierra 10011 201 0x53 0x73
G 7 Golf 00111 021 0x47 0x67 T 20 Tango 10100 202 0x54 0x74
H 8 Hotel 01000 022 0x48 0x68 U 21 Uniform 10101 210 0x55 0x75
I 9 India 01001 100 0x49 0x69 V 22 Victor 10110 211 0x56 0x76
J 10 Juliett 01010 101 0x4A 0x6A W 23 Whiskey 10111 212 0x57 0x77
K 11 Kilo 01011 102 0x4B 0x6B X 24 Xray 11000 220 0x58 0x78
L 12 Lima 01100 110 0x4C 0x6C Y 25 Yankee 11001 221 0x59 0x79
M 13 Mike 01101 111 0x4D 0x6D Z 26 Zulu 11010 222 0x5A 0x7A

In general, numbers in the following ranges can represent ASCII codes:

  • The range 48–57 (0x30–0x39) represents digits, where 48 is '0' and 57 is '9'.
  • The range 65–90 (0x41–0x5A) represents uppercase letters, where 65 is 'A' and 90 is 'Z'.
  • The range 97–122 (0x61–0x7A) represents lowercase letters, where 97 is 'a' and 122 is 'z'.

Sometimes, pictoral encodings will just use letters for A = 1, B = 2, etc. with a prefix to show that they're numbers and not letters.
For example, Semaphore symbol for a number is the sign for a number in semaphore, and Braille symbol for a number is the sign for a number in braille.

Numerical encodings

To view an image that contains every letter for a particular encoding, click the heading for that encoding.
Letter Telephone
digits
Morse Code Maritime
flags (ICS)
Maritime
flags (NATO)
American Sign
Language
0
1
2 ABC
3 DEF
4 GHI
5 JKL
6 MNO
7 PQRS
8 TUV
9 WXYZ
Learn more about Telephone digits
Learn more about Morse Code
Learn more about Maritime flags (ICS)
Learn more about Maritime flags (NATO)
Learn more about American Sign Language

Common Representations of Letters and Numbers

Morse Code Tree

The following diagram is a handy way to quickly decipher Morse code letters. From the node labeled "start," travel downward across dotted or dashed lines accordingly. For example, following the dotted line twice and the dashed line once will lead to the letter U, which is represented by "dot-dot-dash" in Morse code. (Missing nodes indicate invalid Morse code letters.)

start E T I A N M S U R W D K G O H V F L P J B X C Y Z Q

Semaphore Chart

The following chart can be used to help decode semaphore quickly. If the two flags form a straight line, use the smaller circle on the left to determine the correct letter. Otherwise, find the appropriate pie slice among the other six circles corresponding to the two directions.

X Q S I Y M W # T O H A G Z U C E N K V P J B F R D L

Pigpen Cipher

The Pigpen cipher, developed by the Freemasons for secret communication, encodes each letter as a symbol. The encoding is described by the grids below: each letter is encoded by replacing it with the symbol corresponding to the part of the grid that contains the letter.

Pigpen key

For example:

Pigpen example

Roman Numerals

The ancient Romans used letters to represent numbers and had specific rules for combining them:

# Value
I 1
V 5
X 10
L 50
C 100
D 500
M 1000

Ciphers and rotations

Sometimes, letters will be subsituted for other letters, and you'll need to figure out what the mapping is. One common method is a Caesar cipher, or rotation cipher, where every letter in the alphabet is "rotated" or moved down a certain number of letters. For example, rotating by 1 gives:

Input:  ABCDEFGHIJKLMNOPQRSTUVWXYZ
Output: BCDEFGHIJKLMNOPQRSTUVWXYZA

Rotating by 5 gives:

Input:  ABCDEFGHIJKLMNOPQRSTUVWXYZ
Output: FGHIJKLMNOPQRSTUVWXYZABCDE

Or, rotating by 13 gives:

Input:  ABCDEFGHIJKLMNOPQRSTUVWXYZ
Output: NOPQRSTUVWXYZABCDEFGHIJKLM

Colors

Rainbow Order

Rainbow order is the order that colors appear in the color spectrum. If you see these colors in a puzzle, try reading partial answers in rainbow order. A common mnemonic to remember the order is Roy G. Biv.

# Color
1 Red
2 Orange
3 Yellow
4 Green
5 Blue
6 Indigo
7 Violet

Resistor Color Codes

Electrical resistors use color bands on them to indicate their resistance values. This can serve as a good way to convert colors to digits.

# Color
0 Black
1 Brown
2 Red
3 Orange
4 Yellow
5 Green
6 Blue
7 Violet
8 Gray
9 White

Mixing Colors

When using pigments like paints, adding colors together makes them darker.


Pigment combination

Light, on the other hand, combines to create white.

Light combination

Symbols

Here are some other symbols you may see and need to figure out how to use.

Astrological symbols

Sign Name
Aries
Taurus
Gemini
Cancer
Leo
Virgo
Libra
Scorpio
Sagittarius
Capricorn
Aquarius
Pisces

Chinese Zodiac

Sign Name
Rat
Ox
Tiger
Rabbit
Dragon
Snake
Horse
Goat
Monkey
Rooster
Dog
Pig

Planets

Sign Name
Sun
Moon
Mercury
Venus
🜨 Earth
Mars
Jupiter
Saturn
Uranus
Neptune
Pluto

Moon Type

Letter Symbol
A
B
C
D
E
F
G
H
I
J
K
L
M
N
O
P
Q
R
S
T
U
V
W
X
Y
Z
#

Greek Alphabet

Symbol Letter
Α α alpha
Β β beta
Γ γ gamma
Δ δ delta
Ε ε epsilon
Ζ ζ zeta
Η η eta
Θ θ theta
Ι ι iota
Κ κ kappa
Λ λ lambda
Μ μ mu
Ν ν nu
Ξ ξ xi
Ο ο omicron
Π π pi
Ρ ρ rho
Σ σ sigma
Τ τ tau
Υ υ upsilon
Φ φ phi
Χ χ chi
Ψ ψ psi
Ω ω omega