Letters To Numbers
Convert letters to numbers instantly with A1Z26, A0Z25, reversed alphabet, T9 phone keypad, ASCII, Hex ASCII, and Binary ASCII. Free online letter-to-number converter for puzzles and ciphers.
About This Calculator
The Letters To Numbers Converter is a versatile text encoding tool that transforms any text into its numeric representation using multiple encoding methods. Whether you're solving a puzzle cipher, learning about character encoding, creating secret messages, or exploring how computers represent text, this converter supports A1Z26 (A=1, B=2), A0Z25 (A=0, B=1), reversed alphabet Atbash-style mapping, T9 phone keypad digits, standard ASCII/Unicode code points, Hex ASCII, and Binary ASCII formats.
Each encoding method has its own use case. A1Z26 is popular in escape rooms, geocaching puzzles, and educational cryptography activities. ASCII encoding shows how computers store text as numbers — each character has a unique numeric value between 0 and 127 for standard ASCII. The T9 phone keypad method maps letters to telephone digits, useful for decoding phonewords like 1-800-FLOWERS. Binary ASCII reveals the underlying 8-bit binary patterns that computers use to represent text internally.
The converter processes every character individually and displays a complete breakdown table showing each character alongside its encoded value. The bar chart visualizes the numeric values of each character position, while the pie chart shows the frequency distribution of encoded values across your text.
Regional Notes
India: The A1Z26 cipher is used in Indian puzzle competitions and treasure hunts. ASCII encoding is universal for digital text processing across all regions.
US: T9 phone keypad encoding is commonly used in US advertising with phonewords like 1-800-FLOWERS. A1Z26 puzzles appear in popular escape rooms across the country.
UK: The UK uses the same ASCII and T9 standards. Letter-to-number puzzles are featured in British puzzle hunts and cryptography challenges.
Frequently Asked Questions
How do I convert letters to numbers?
Enter your text and choose an encoding method. A1Z26 assigns each letter its alphabet position (A=1, B=2, ..., Z=26). A0Z25 uses zero-based indexing (A=0, B=1, ..., Z=25). ASCII uses standard character codes, and the T9 method maps letters to phone keypad digits (ABC=2, DEF=3, etc.).
What is the A1Z26 cipher?
The A1Z26 cipher replaces each letter with its position in the alphabet: A=1, B=2, C=3, and so on up to Z=26. It is one of the simplest letter-to-number substitution ciphers, often used in puzzles, escape rooms, geocaching, and cryptography challenges.
How does the T9 phone keypad conversion work?
The T9 phone keypad maps letters to digits: ABC=2, DEF=3, GHI=4, JKL=5, MNO=6, PQRS=7, TUV=8, WXYZ=9. This system was used on traditional mobile phones for text input and is still used for phonewords like 1-800-FLOWERS.
How do I convert letters to binary?
Select the Binary ASCII encoding method. Each character is converted to its ASCII code point, then translated into an 8-bit binary value. For example, 'A' has ASCII code 65, which becomes 01000001 in binary.
What is the difference between A1Z26 and A0Z25?
A1Z26 uses 1-based indexing where A=1 and Z=26. A0Z25 uses zero-based indexing where A=0 and Z=25. A0Z25 is commonly used in programming contexts where arrays start at index 0, while A1Z26 is more intuitive for puzzles and educational activities.
How do I decode numbers back to letters?
To decode numbers back to letters using A1Z26, reverse the mapping by converting each number to the corresponding alphabet position (1=A, 2=B, ..., 26=Z). For ASCII, use String.fromCharCode() to convert code points back to characters.
Can I convert uppercase and lowercase letters?
For A1Z26, A0Z25, reversed alphabet, and T9 methods, uppercase and lowercase letters produce the same result since the mapping is case-insensitive. For ASCII, Hex ASCII, and Binary ASCII, uppercase and lowercase letters have different code points (e.g., 'A'=65, 'a'=97).
What is reversed alphabet encoding?
Reversed alphabet encoding flips the standard order: A=25, B=24, C=23, ..., Z=0. It is a simple substitution cipher where the alphabet is mirrored, sometimes called the Atbash cipher for the Latin alphabet when applied to individual letters.