A1Z26 Cipher

Convert letters to numbers with A1Z26

The A1Z26 cipher is one of the simplest codes, replacing each letter with its position in the alphabet: A becomes 1, B becomes 2, and so on up to Z as 26. This tool encodes text into numbers, separating the numbers within each word with dashes and keeping words apart with spaces, and decodes numbers back into letters. For example, the word ABC encodes to 1-2-3. It is a staple of puzzles, escape rooms and beginner cryptography.

Spaces separate words so the decoder knows where one word ends and the next begins.

A gentle introduction to codes

Because the A1Z26 cipher maps directly onto the familiar alphabet, it is often the first code children and newcomers learn, and it appears frequently in treasure hunts, geocaching and puzzle games. It offers no security, since anyone can read it with the obvious key, but that simplicity is exactly why it is popular for fun and teaching.

The encoder ignores non-letter characters and the decoder accepts dashes, commas or dots between the numbers, making it forgiving of different puzzle formats. All processing happens locally in your browser.

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