A1Z26 cipher
A is 1, B is 2, all the way to Z is 26. Letters to numbers and back.
Chart A=1
- A1
- B2
- C3
- D4
- E5
- F6
- G7
- H8
- I9
- J10
- K11
- L12
- M13
- N14
- O15
- P16
- Q17
- R18
- S19
- T20
- U21
- V22
- W23
- X24
- Y25
- Z26
How A1Z26 works
A1Z26 replaces each letter with its place in the alphabet: A is 1, B is 2, up to Z, which is 26. Numbers in the result are joined with hyphens, and words are separated by a slash.
Some versions start at zero, so A is 0 and Z is 25. Pick that key, or make one of your own: choose the number for A and a step per letter. With A as 5 and a step of 5, N becomes 70.
If you know two letters and their numbers, you can find the step yourself: E as 25 and I as 45 are four letters apart, and the numbers are 20 apart, so the step is 5 and A is 5.
Digits in a message cannot be encoded, because a plain 1 would be mistaken for the letter A. Write them out as words.
Example: HELLO
With A as 1, each letter becomes its place in the alphabet:
8-5-12-12-15
Other ciphers
Letters can also swap with other letters, as in ROT13 and the Atbash cipher, or turn into digit pairs with the Polybius square. All of them are on the scout codes page.