A1Z26 cipher decoder

The A1Z26 cipher got its name from the way it works: A=1, B=2, ..., Z=26. It is the simplest possible letters to numbers translation. Although the encoding is intended for the English alphabet, it can easily be used for other languages as well. This translation tool will help you easily decode A1Z26 codes to letters using any alphabet.

A1Z26 cipher, or variants of letters to numbers, is frequently used in geocaching mystery caches (puzzle caches), CTFs and logic puzzles.

What is the A1Z26 cipher?

The A1Z26 cipher is a simple substitution cipher where each letter of the alphabet is replaced by its position in the alphabet (A=1, B=2, ..., Z=26 or similar for other alphabets). Sometimes spaces or punctuation are replaced by 0, kept as-is, or omitted entirely depending on the format.

Sample A1Z26 Cipher

Code-breaking is not only fun, but also a very good exercise for your brain and cognitive skills. Why don’t you try this example cipher:

9 23 9 12 12 18 5 20 21 18 14 20 15 20 8 5 5 13 5 18 1 12 4 3 9 20 25 8 5 18 5 16 12 9 5 4 6 15 18 15 26 8 1 19 13 1 4 5 13 5 9 20 19 18 21 12 5 18 1 14 4 20 8 5 16 5 15 16 12 5 12 9 11 5 13 5