Numbers to Letters Calculator — A1Z26 Cipher
Convert any sequence of numbers to their matching alphabet letters using the A1Z26 code: 1=A, 2=B, 3=C … 26=Z. Enter your numbers separated by spaces or commas and the letters appear instantly.
How does this calculator work?
In the A1Z26 code, each letter equals its alphabet position: A=1, B=2 … Z=26. To decode, enter numbers 1–26 separated by spaces. Example: "8 5 12 12 15" → HELLO. Numbers outside 1–26 have no match. This is a one-to-one substitution with no encryption strength — it is purely a convenient notation.
Formula
How this is calculated
The A1Z26 substitution assigns each letter of the English alphabet a number equal to its position: A=1, B=2, C=3 … Z=26. To decode a number back to its letter, look up that position in the alphabet, or equivalently compute the Unicode character at code point 64 + N (since A is code point 65).
This calculator accepts any sequence of integers from 1 to 26 separated by spaces or commas. Each number is independently converted to its corresponding letter and the results are concatenated into a word or phrase. For example, "8 5 12 12 15" decodes to "HELLO" because H=8, E=5, L=12, L=12, O=15.
A1Z26 is one of the simplest ciphers and is often used in puzzles, escape rooms and educational activities. It has no cryptographic strength — anyone who knows the scheme can decode it immediately — but it remains a popular encoding for casual games and classroom exercises.
Frequently asked questions
A1Z26 is a simple substitution cipher where A=1, B=2, C=3 and so on through Z=26. The name comes from the first letter (A=1) and last letter (Z=26) of the alphabet.
Numbers below 1 or above 26 do not correspond to any standard English letter and the calculator will return no result. Split multi-digit numbers (like 12 for L) with a space or comma rather than running them together.
Yes — for that direction, note that A=1, B=2 … Z=26. For example, "MATH" converts to "13 1 20 8". You can use this as a reverse lookup table.
Also known as
TG we-Calculate Editorial Team. (2026). Numbers to Letters Calculator — A1Z26 Cipher [Online calculator]. TG we-Calculate. https://we-calculate.com/calculator/numbers-to-letters-calculator
TG we-Calculate Editorial Team. "Numbers to Letters Calculator — A1Z26 Cipher." TG we-Calculate. 2026. https://we-calculate.com/calculator/numbers-to-letters-calculator.
TG we-Calculate Editorial Team, "Numbers to Letters Calculator — A1Z26 Cipher," TG we-Calculate, 2026. [Online]. Available: https://we-calculate.com/calculator/numbers-to-letters-calculator
@misc{wecalculate_numbers_to_letters_calculator, title = {Numbers to Letters Calculator — A1Z26 Cipher}, author = {{TG we-Calculate Editorial Team}}, howpublished = {\url{https://we-calculate.com/calculator/numbers-to-letters-calculator}}, year = {2026}, note = {TG we-Calculate} }
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