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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.

Letter	Morse Code	Semaphore	Braille	Maritime flags	American Sign Language	Letter	Morse Code	Semaphore	Braille	Maritime flags	American Sign Language
A						N
B						O
C						P
D						Q
E						R
F						S
G						T
H						U
I						V
J						W
K						X
L						Y
M						Z

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.)

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.

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.

For 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.

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

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
子	Rat
丑	Ox
孜	Tiger
卯	Rabbit
辰	Dragon
巳	Snake
午	Horse
未	Goat
申	Monkey
酉	Rooster
戌	Dog
亥	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