Transforms & generators
A1Z26 cipher decoder
A=1 … Z=26. Encode a message or decode a list of numbers.
Processed in your browser — nothing is uploaded
Encode maps letters to numbers. Decode reads integers 1–26 and emits letters. Non-letters pass through.
Last reviewed 2026-09-10.
FAQ
Questions, answered
Is this encryption?
No. It is a classroom cipher anyone can reverse.
Spaces?
Spaces stay as separators so decoded words remain readable.
Does my text leave the browser?
No. The A1Z26 tool runs in JavaScript on this page. Your paste is not uploaded.
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