Alphabet positions / A=1 to Z=26

A1Z26 cipher

Encode ASCII letters as alphabet positions or strictly decode numbered words without guessing the direction or format.

01 / Workspace

Encode or decode

Dash separated
Direction

Encode maps ASCII A-Z in either case to values 1 through 26.

This separates letter values inside each word. A slash separates words in both formats.

A1Z26 numbers contain no case information, so Decode uses this explicit choice.

0 / 5,000 code points

Use ASCII letters and ASCII whitespace only. Whitespace runs become word boundaries; digits, punctuation, accents, non-Latin letters, and emoji are rejected.

Keyboard shortcut: Ctrl+Enter or Command+Enter runs the selected direction.

Ready to encode.

02 / Result

Result

No result yet
0 code points

Letter values use dashes. A standalone slash marks each normalized word boundary.

03 / Rules

Exact A1Z26 convention

  1. Map the English alphabet. A is 1, B is 2, and Z is 26. Encoding is case-insensitive and decoding returns the selected uppercase or lowercase form.
  2. Keep words explicit. Encoding collapses every run of ASCII whitespace to one / boundary. It never silently removes unsupported characters.
  3. Decode one grammar. Values must be unpadded decimal integers from 1 through 26. The selected dash or ASCII-whitespace separator divides letters, and slash alone divides words.

Known check

ABC XYZ encodes with dashes as 1-2-3 / 24-25-26. Decoding that sequence in uppercase returns ABC XYZ.

Limits and security

  • Encoding accepts only ASCII A-Z, a-z, and ASCII whitespace. Every digit, punctuation mark, accented letter, non-Latin letter, emoji, and other non-ASCII character causes an error and remains in the input for correction.
  • Decoding ignores ASCII whitespace at the outer edges and around slashes. In space-separated mode, ASCII whitespace also separates values. Leading zeros, decimals, signs, empty words, repeated slashes, and values outside 1 through 26 are rejected.
  • Original letter case, whitespace type, whitespace count, and line breaks cannot be recovered. Browser text controls normalize CR and CRLF line endings to LF before processing.
  • Input is limited to 5,000 Unicode code points and 10,000 UTF-16 code units so repeated actions remain responsive. Invalid or oversized input is preserved.
  • A1Z26 is a classical puzzle cipher for education and recreation. It has no secret key and is unsuitable for protecting sensitive information.