A1Z26 Cipher - Letter Number A=1 B=2 C=3 - Online Decoder, Translator https://www.dcode.fr/letter-number-cipher
How to encrypt using Letter-to-Number cipher?
A1Z26 encryption requires to count the positions/ranks of letters in the alphabet. If it is the Latin alphabet of 26 characters here is the correspondence table letter ↔ number/value:
| 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 |
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 |
Replace each letter with its position in the alphabet (A = 1, B = 2, ... Z = 26)
Example: DCODE is encrypted 4-3-15-4-5 by alphanumeric substitution
How to decrypt Number-to-Letter cipher?
Decryption requires taking each number and replace it with the letter of same position in the alphabet: 1 = A, 2 = B, ... 26 = Z
| 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 |
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 |
Example: 1.12.16.8.1.2.5.20 gives ALPHABET
How to recognize Letter-to-Number ciphertext?
The crypted message is made of numbers between 1 and 26, sometimes the number 0 is used to code a space.
The digit 5 for E is supposed to appear regularly for an english text.
This encryption is sometimes called alphanumeric code.
What are the variants of the Letter-to-Number cipher?
Shift of numbers: the alphabet can start with A = 0 or A = 1, but also A = 65 or A = 97 (ASCII code).
Use of a supplementary character for space (usually 0 or 27)
Use of leading zeros to be able to concatenate numbers AB = 0102, else AB = 12 and 12 = L.
Use of a custom alphabet, or reversed alphabet (A=26, Z=1)
Use of modulo 26 in order to get 1=A,2=B,...26=Z then 27=A, 28=B etc.