🔢 Letter to Number Converter

What is the Letter to Number Converter?

This kind of conversion is often called A1Z26, a shorthand for the rule that A maps to 1 and Z maps to 26. It is one of the simplest substitution systems in existence: every letter of the alphabet gets a fixed, unchanging number, so the same letter always produces the same digit no matter where it appears in a word. Because the mapping never changes and never depends on a secret key, A1Z26 is not really a cipher in the cryptographic sense, it is closer to a numbering scheme or a simple encoding, similar in spirit to a lookup table.

People reach for a letter to number converter for a handful of very different reasons. Puzzle and escape room designers use A1Z26 constantly because it is easy to explain to a solver with a single alphabet chart, yet still requires a small amount of decoding effort. Students and hobbyists studying basic cryptography use it as a first, gentle example before moving on to genuinely secret-key systems like the Caesar cipher or Vigenere cipher, both of which build on the same idea of mapping letters to numbers before doing arithmetic on them. Numerologists use a version of the same table to reduce names and words down to digits for their own systems, and word game and trivia writers use it to hide a phrase in plain sight, since the numbers look meaningless until someone tries the alphabet mapping.

This tool is case-insensitive by design: uppercase and lowercase versions of the same letter always produce the same number, since "H" and "h" occupy the same position in the alphabet. Only the 26 letters of the basic Latin alphabet are converted. Accented letters (such as e with an accent), and letters from non-Latin alphabets such as Greek, Cyrillic, or Chinese characters, are not part of the A to Z sequence this tool uses, so they are treated the same as any other non-letter character, either passed through unchanged or skipped depending on your settings.

One honest limitation worth knowing before you rely on the output: when the separator is set to "None," the numbers are simply glued together with nothing between them, and that can be genuinely ambiguous to read back by hand. For example, the digits "1" and "12" concatenated with nothing between them look identical to "1" followed by "2", so "112" could mean the letters A, L (1, 12) or A, A, B (1, 1, 2). If you plan to decode the output later, a visible separator (space, comma, or hyphen) removes that ambiguity completely, while "None" should be reserved for cases where you only need a compact numeric fingerprint of the text rather than a reversible code.

When to use it

• Designing or solving puzzle hunts and escape rooms that hide a word or phrase behind an A1Z26 number sequence.
• Teaching an introductory cryptography or coding lesson, using A=1 to Z=26 as the first, simplest example before Caesar or Vigenere ciphers.
• Turning a name or word into digits for numerology-style calculations or personal number games.
• Generating a quick, reversible numeric code for a username, password hint, or private note (paired with the matching number to letter converter to decode it later).
• Checking your own hand-worked A1Z26 puzzle answers for mistakes before publishing or submitting them.
• Exploring how substitution-style encodings work as a stepping stone to understanding modern character encoding schemes like ASCII.

How to use the Letter to Number Converter

1. Type or paste your text into the box. The default example "HELLO" already shows a real result so you can see the format immediately.
2. Pick a separator from the dropdown: space, comma, hyphen, or none, depending on how you want the numbers displayed.
3. Leave "Skip non-letters" ticked to ignore spaces, punctuation, and digits, or untick it to keep them in the output exactly as typed.
4. Read the result the moment you stop typing, since the conversion updates live with no button to press.
5. Click "Copy result" to copy the number sequence to your clipboard for pasting into a puzzle, message, or spreadsheet.

Formula & method

Worked examples

Full A to Z alphabet position table (the mapping this tool uses)

What each setting does to non-letter characters and output format

Common mistakes to avoid

• Using "None" as the separator and then losing track of word boundaries. With no separator, "1" and "12" glued together are indistinguishable from "1" then "2". If you need to hand this off to someone to decode, always use a visible separator (space, comma, or hyphen) instead of "None," which is best reserved for a compact fingerprint rather than a reversible code.
• Expecting accented letters or non-Latin scripts to convert. This tool only maps the 26 basic Latin letters A to Z. An accented letter, or a character from Greek, Cyrillic, or another script, is treated as a non-letter, so it is either skipped or passed through unchanged rather than assigned a number.
• Assuming uppercase and lowercase give different numbers. The conversion is case-insensitive by design, matching the standard A1Z26 convention. "H" and "h" both convert to 8, since they occupy the same position in the alphabet regardless of case.
• Treating A1Z26 as a secure or secret code. Because the letter to number mapping never changes and uses no key, anyone who knows the basic rule (A=1, Z=26) can reverse it instantly. It is fine for puzzles, games, and teaching, but it provides no real security or privacy for sensitive information.

Glossary

A1Z26

A common name for the simple substitution scheme where A=1, B=2, and so on through Z=26, used widely in puzzles and introductory cryptography.

Alphabet position

The numbered place a letter occupies in the standard 26-letter Latin alphabet, counting A as position 1 and Z as position 26.

Separator

The character or string placed between each converted number in the output, such as a space, comma, or hyphen.

Substitution scheme

A system that replaces each symbol in a message with another fixed symbol or value, following a consistent rule rather than a randomly assigned key.

Skip non-letters

A setting that removes spaces, digits, and punctuation from the input before conversion, so only the letter-derived numbers appear in the result.

Reversible code

An encoding where the original text can be recovered exactly from the output, which for A1Z26 requires a clear separator between numbers.

Frequently asked questions