Letters to Numbers Converter

If you've ever wondered how to convert letters to numbers, decode a secret message, or explore the logic behind the classic A1Z26 cipher, our intuitive letters to numbers converter opens the door to a fascinating world of text encoding.

Such transformations aren't just theoretical; the letters to numbers transformation is still often used in mystery geocaches (puzzle caches), cybersecurity contests, escape rooms, educational puzzles, alternate reality games (ARGs), and logic games, where quick pattern recognition is crucial. Our versatile alphabet to numbers converter allows you to experiment with ciphers, understand historical encoding systems, and explore how letters and numbers have been interconnected for centuries.

Scroll down to find out more:

• How to convert letters to numbers;
• A1Z26 cipher explained;
• Letters to numbers chart;
• How to convert letters to telephone numbers; and
• How to use Omni's letters to numbers converter.

The idea behind converting letters to numbers is straightforward: each letter is assigned a numerical value based on a specific rule or pattern. Depending on the alphabet, the direction, or the purpose of the code, you might convert letters to numbers using zero-based indexing, reversed alphabets, or even special systems like telephone keypad mappings to turn phone number letters to numbers. To help visualise these patterns, many people rely on a letter-to-numbers chart, which shows how each character corresponds to its numeric value.

The A1Z26 cipher

The A1Z26 cipher is the simplest letter-to-number substitution system: each letter is replaced by its position in the alphabet, so $A=1, B=2, C=3$, and so on up to $Z=26$. It makes no distinction between uppercase and lowercase, and the space character is typically assigned the value $0$. To see this pattern, let's take a look at a letters to numbers chart for the A1Z26 cipher in the Latin alphabet:

For example, the phrase "Hello world" in A1Z26 cipher for Latin alphabet becomes:

H=8, E=5, L=12, L=12, O=15, (space)=0, W=23, O=15, R=18, L=12, D=4
→ 8 5 12 12 15 0 23 15 18 12 4

The same principle applies to other alphabets as well: whether you're converting Arabic letters to numbers, Greek letters to numbers, or working with a different script entirely, you can assign numerical values to letters in their natural order.

Zero-based indexing (A0Z25)

The idea is the same as in the A1Z26 cipher, but to convert letters to numbers, you shift the mapping so that $A=0, B=1, C=2$, and so on up to $Z=25$.

Reversed alphabet

In the reversed alphabet pattern, the mapping is flipped: $A$ receives the highest value ($25$) and $Z$ the lowest ($0$). However, the rule for converting letters to numbers stays the same; you assign values based on the reversed order of the alphabet. If you'd like to experiment with flipped or mirrored text more broadly, try our backwards text generator.

ASCII / Unicode

Instead of using alphabetical position, this method converts letters to numbers by taking their ASCII (or Unicode) code point, which uniquely identifies each character in digital systems. For a quick example, the word "Apple" in ASCII format becomes 65 112 112 108 101.

If you'd like to explore full tables of ASCII, hexadecimal, or binary code points, check our dedicated ASCII converter.

Hex ASCII / Unicode

Hex ASCII follows the same idea as ASCII encoding, but the character's code point is expressed in hexadecimal, a base-16 numbering system commonly used in computing. The same word "Apple" in hexadecimal ASCII becomes 41 70 70 6C 65.

Binary ASCII / Unicode

Binary ASCII represents each character's code point in binary form, showing the underlying $0–1$ pattern used by digital devices to store and process text. And finally, "Apple" in binary ASCII format is 01000001 01110000 01110000 01101100 01100101.

Before smartphones, mobile phones relied on the T9 keypad system, where several letters were grouped under a single digit. Converting phone number letters to numbers is still a common puzzle mechanic, and it follows a fixed mapping:

Let's look at the letters to numbers chart above. With this mapping in mind, you can see that if you convert letters to telephone numbers, the word "BIRTHDAY" becomes 24784329 using the standard T9 layout. For more ways to play with this type of mapping, visit our T9 to text converter.

Omni's alphabet to numbers converter works automatically as you type. Here's how to convert letters to numbers with our tool:

1. Enter your text. Simply type or paste your letters into the textbox.
2. Select the encoding method. Choose between the A1Z26 cipher, zero-based indexing (A0Z25), reversed order, ASCII, Hex ASCII, Binary ASCII, or convert letters to telephone numbers with the telephone keypad (T9) mapping.
3. Choose the alphabet type. Pick from the supported alphabets (Latin, Greek, Cyrillic, Hebrew, Arabic).
4. Read the encoded text. The result appears instantly below the letters-to-numbers converter.

And that's all! If you're interested in reverse operation, explore our numbers to letters converter.