Numbers to Letters Converter

Our numbers to letters converter is designed to translate numbers into letters through various coding methods, including alphabet-based methods, ASCII formats, T9 phone keypad mapping, and even periodic table notation, allowing you to decode numeric messages instantly.

Turning numbers into letters is a simple but powerful encoding method, used in everything from puzzles and ciphers to phone keypads and digital systems. By exploring these systems, you can learn how a numbers to letters code works and how people have combined numerical and alphabetical symbols in creative and practical ways throughout history.

Continue reading to discover:

• How to convert numbers to letters using different coding systems;
• Where to use binary numbers to letters conversion;
• Why phone numbers to letters mappings are used on keypads; and
• How our numbers to letters converter works.

A numbers to letters code is simply a way of turning numbers into text based on a specific rule or pattern. You’ve probably seen versions of it before: puzzles where $A=1, B=2, C=3$; phone keypads that turn digits into words; or digital systems that use numbers to represent characters. The idea is always the same: numbers stand in for letters, allowing a message to be stored, hidden, or transmitted in a different form. In fact, many of these methods can be viewed as forms of a substitution cipher, where one symbol is swapped for another according to a fixed rule. Different systems do this in various ways:

Basic A1Z26 cipher (A=1,..., Z=26)

The most recognizable method of translating numbers to letters is where each letter is represented by its position in the alphabet: $A=1, B=2, ..., Z=26$. If you want to try it yourself, take a look at the full A1Z26 table below:

Uppercase and lowercase letters are treated the same, and zero is often used to represent a space, so that you can separate words directly in the numeric message. Let's try a quick example: if your coded sequence is 6 21 14 0 20 9 13 5, then after converting the numbers to letters, you'll get " FUN TIME".

Zero-based indexing (A0Z25)

In this variation, letters start counting from zero instead of one: $A=0, B=1, ..., Z=25$. However, because $0$ already represents the letter $A$, you can't use it as a space marker in this system.

Let's review the previous sequence again: 6 21 14 0 20 9 13 5. When translating numbers to letters with the A0Z25 cipher instead of A1Z26, we end up with the string GVOAUJNF, which appears to be gibberish. This happens because A0Z25 is a zero-based system, so every letter is shifted by one position compared to the standard A1Z26 mapping.

Reverse alphabet

It means that the alphabet is flipped so that numbering starts from the end rather than the beginning: $Z=0, Y=1, X=2$, and so on until $A=25$. Because the count begins with $0$ at the last letter, each number points to the mirrored position in the alphabet.

ASCII / Unicode

This method, often used in computing and digital communication, relies on character codes instead of alphabet positions: each number corresponds to a specific character in the ASCII or Unicode table. For example, entering $74$ returns $J$ because $74$ is the ASCII value for that letter. Complete ASCII, Hex ASCII, and Binary ASCII tables are available in our ASCII charts.

Hex ASCII / Unicode

In this method, character codes are written in hexadecimal (base-16) notation, which uses the digits $0–9$ and the letters $A–F$. It still follows the same idea of a numbers-to-letters code; each hex value matches a specific character in the ASCII or Unicode table. The letter $J$, to illustrate, corresponds to $4A$ in hex, since hex $4A$ represents the same numeric value as decimal $74$ in the ASCII table.

Binary ASCII / Unicode

In this variation, characters are represented using base-2 values. In other words, it's simply a binary numbers to letters conversion. For example, $01001010$ translates to $J$ because it represents the binary form of the ASCII value $74$ — you can verify this instantly with our binary to decimal converter.

The traditional T9 keypad system turns phone numbers to letters by interpreting repeated digits as specific characters, and pressing the same digit multiple times cycles through them. Before touchscreens and full QWERTY keyboards became standard, this method was widely used for writing text on phones. At that time, it was surprisingly efficient because it allowed users to type quickly using only a small set of physical keys. See the standard T9 keypad mapping below:

Our numbers-to-letters converter follows this pattern: entering sequences like 3 666 4 produces the word "DOG". This method remains a classic way of converting telephone numbers to letters, demonstrating how simple numeric input can be transformed into clear text. If you want a tool that works in both directions, try our T9 to text converter.

You've probably come across those cheesy periodic table puns, like "Are you copper and tellurium? Because you're Cu–Te!" Similarly, you can encode messages, creating a playful numbers to letters code, where atomic numbers stand in for letters: $\rm H=1, He=2, Li=3$, and so on down the periodic table. By writing a sequence of atomic numbers instead of letters, you can hide a word behind element symbols in a fun and unusual way. To explore element data further, try our atomic mass calculator.

For instance, the numeric sequence 6 1 8 27 57 52 can be decoded into element symbols as C–H–O–Co–La–Te, which together spell "ChOCoLaTe." Another possible numbers to letters code for the same word, based on alternative element choices, is 6 67 27 57 52.

It's a playful way to disguise a message using chemistry instead of a regular alphabet.

Using our numbers to letters converter is really simple, just follow these steps:

1. Enter your numbers. Type or paste any sequence of numbers separated by spaces or commas.
2. Choose the decoding method. Select one of the available systems:
   • A1Z26;
   • Zero-based indexing (A0Z25);
   • Reversed alphabet;
   • ASCII;
   • Hex ASCII;
   • Binary ASCII;
   • Phone numbers to letters (T9); or
   • Periodic table notation.
3. Select the alphabet (if needed). Some methods let you switch between Latin, Greek, Cyrillic, Hebrew, or Arabic alphabets.
4. Read the decoded text. Your output appears instantly as the numbers are converted into letters.

Ready to go the other way? Click here to convert letters to numbers.