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A1Z26 Cipher Decoder (Numbers ↔ Letters)

Enter numbers like 8 5 12 12 15 and you get HELLO, or type a word to get its number string. It handles both the standard A=1 and the reversed Z=1 keys.

Estimates for general information, verify important figures before relying on them.
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Common values

LetterNumber (A=1)
A1
E5
H8
M13
Z26

Common questions

What is the A1Z26 cipher?

It swaps each letter for its position in the alphabet, so A is 1, B is 2, on up to Z at 26. It is a simple substitution used in puzzles and escape rooms.

What is the reversed version?

The reversed key counts from the other end, making Z equal 1 and A equal 26. The decoder supports both directions.

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