A1Z26 Cipher
Convert letters to alphabet numbers and back.
Letters as numbers
The A1Z26 cipher replaces each letter with its position in the alphabet — A is 1, Z is 26. It is a staple of puzzle hunts and escape rooms because it is easy to spot yet fun to decode.
Encoding HELLO gives 8-5-12-12-15, with words kept separate. Switch to decode mode and paste numbers to recover the letters. Non-letters and word breaks are preserved.
Puzzle-friendly and private
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Frequently Asked Questions
What is the A1Z26 cipher?
A simple code where A is 1, B is 2, and so on to Z is 26. It is common in puzzles and escape rooms.
How is decoding handled?
In decode mode, numbers separated by spaces, dashes, or commas are turned back into letters.
What about spaces between words?
Words are separated so the structure survives the round trip in both directions.
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