How the A1Z26 Cipher Works
A1Z26 is the simplest letter-to-number code there is, and it shows up in puzzles everywhere. This guide explains the mapping and how to read it fluently.
What is the A1Z26 Cipher?
A1Z26 Cipher replaces each letter with its position in the alphabet, so A is 1, B is 2, and Z is 26. Encoding separates letters with spaces and words with a slash, and decoding reverses the process, flagging any number outside 1 to 26.
How to use it
- Type text or A1Z26 numbers into the box.
- Choose Encode or Decode.
- Click Encode and copy the result.
Worked example
For 'hello' in Encode mode, the output is '8 5 12 12 15'.
Where is A1Z26 actually used?
Mostly in puzzles, escape rooms, and children's code games, where the fun is in spotting that a string of numbers spells a word. It offers no real secrecy, since the mapping is fixed and public.
Frequently asked questions
How are words separated when encoding?
Letters in a word are separated by spaces and words are separated by a slash, so 'hi there' encodes as '8 9 / 20 8 5 18 5'.
What happens if I enter 27 when decoding?
The tool reports it as an invalid code, since A1Z26 only defines numbers from 1 to 26.