Hex Value Alphabet: A–Z and a–z ASCII Reference Chart

A hex value alphabet chart shows the hexadecimal character codes for English letters. In ASCII, uppercase A–Z runs from 41 to 5A, while lowercase a–z runs from 61 to 7A. Each letter has its own value, so A and a produce different codes.

There is one common source of confusion: letters can also appear inside hexadecimal numbers. The digit A means decimal 10 in base 16, but the text character A has the ASCII code 41. Those are different uses of the same symbol.

The chart below gives all 52 letter values, with decimal codes alongside them. You can use it to convert a name, check a programming exercise, or read alphabetic text in a hex dump. The examples also show how to handle case, spaces, and values outside the English alphabet.

Letter Codes at a Glance

In ASCII, uppercase letters use hexadecimal codes 41–5A, and lowercase letters use 61–7A. For example, A is 41, Z is 5A, a is 61, and z is 7A. These values also represent the same letters in UTF-8, because UTF-8 preserves ASCII byte values.

Complete Hex Alphabet Chart with Decimal Values

Read across each row to compare an uppercase letter with its lowercase partner. The hex columns use base 16; the decimal columns use base 10. They describe the same character codes in different number systems.

All entries are standard ASCII letter codes. They are not alphabet positions such as A=1 and Z=26.

Preserve the letter's case before choosing a column. Looking up M under lowercase gives 6D, which represents m. A decoder would return the wrong case even though that value is valid hex.

The Hexadecimal Alphabet Is Not the English Alphabet

The hexadecimal alphabet contains 16 digits: 0–9 and A–F. It stops at F because those symbols already cover all possible values for one base-16 digit.

An English letter such as G is not a valid hex digit, but it can still have a hexadecimal character code. Its ASCII value is decimal 71, written as 47 in hex. The code uses valid hexadecimal digits to identify a character outside A–F.

The difference is easiest to see with F. Used as a hex digit, F means 15. Used as text, the uppercase character F has ASCII hex 46.

Context decides which meaning applies. A numeric field containing 0xF describes a number. A text field containing F describes a character. Converting that text character to its byte representation gives 46, not 0F.

Reading ASCII Hex Values Without Mixing Number Bases

ASCII stands for American Standard Code for Information Interchange. It defines 128 character codes using seven bits, including English letters, digits, punctuation, and control characters. Those codes are often displayed inside eight-bit bytes with a leading zero bit.

For uppercase R, the ASCII character code is decimal 82. The same value can be written as:

To check the hexadecimal value, multiply its first digit by 16 and add its second digit:

52 in hex = (5 × 16) + 2 = 82 in decimal

The prefix 0x labels a number as hexadecimal in many programming contexts. Therefore, 0x52 and hex 52 describe the same value. The prefix is notation, not an extra part of the character's stored ASCII byte.

Always check column labels. Decimal 52 identifies the character 4, while hexadecimal 52 identifies R. Treating an unlabeled number as the wrong base changes the answer.

Why Uppercase and Lowercase Letters Differ by 20 Hex

Each lowercase ASCII letter sits 32 decimal positions after its uppercase partner. That difference is hexadecimal 20.

For example:

• C is 43; c is 63.
• N is 4E; n is 6E.
• Y is 59; y is 79.

For the English letter pairs in this chart, adding 0x20 changes uppercase to lowercase. Subtracting 0x20 reverses it. This pattern follows the ASCII layout, but it is not a general rule for every language or every character.

There is also a separate kind of case: the letters used to write the hex number itself. Hex 4E and 4e are numerically equal. Both identify uppercase N. Lowercase n requires 6E or 6e.

That distinction matters when comparing encoded strings. Changing 4E to 4e changes the display style of the number. Changing 4E to 6E changes the decoded character. In software that handles international text, use appropriate string case-conversion methods rather than applying ASCII arithmetic to arbitrary input.

Convert Alphabet Letters to Hex and Decode Them Back

To convert alphabet to hex manually, look up each character in order and write its two-digit value. Preserve uppercase and lowercase letters, and include spaces when they belong to the text.

Take the name Maya:

The result is 4D 61 79 61, or 4D617961 without separators.

For MAYA, the result changes to 4D 41 59 41. Three values differ because three letters changed case.

To convert hex to letters, reverse the lookup:

1. Split a continuous byte string into pairs from the left.
2. Interpret every pair as a hexadecimal byte value.
3. Find the matching character in the ASCII table.
4. Keep the original order and case.

For example, 52 65 61 64 decodes to Read. Do not interpret 52 as decimal 52 or split it into two separate characters.

For a two-digit pair, the numeric value is 16 × first digit + second digit, using decimal values 10–15 for A–F. If the decoded value is outside the letter ranges, consult the full ASCII table or the correct text encoding instead of assuming the input is wrong.

Spaces, Digits, and Symbols Beside the Letters

Real text rarely consists only of letters. A useful letter to hex reference also needs a few neighboring codes:

The string Go 7! becomes 47 6F 20 37 21. Here, 20 represents the actual space between the words, while the spaces between byte pairs are display separators.

Notice that the text character 7 uses 37. A raw byte with the numeric value 7 would instead be 07, an ASCII control character.

This is why a missing 20 can join two words, while a missing display separator may leave the decoded text unchanged. The important question is whether you removed a byte value or merely changed how the values were formatted.

Check Letter Codes with Python or JavaScript

A short program can verify the chart and prevent lookup errors.

Python: ord(), format(), and chr()

Python's ord() returns a character's Unicode code point. For ASCII letters, that value is also the ASCII code. Use hexadecimal formatting to display it:

letter = "R"
value = ord(letter)
print(value)                 # 82
print(format(value, "02X"))  # 52
print(chr(int("52", 16)))    # R

To inspect a whole ASCII word:

word = "Maya"
print(" ".join(format(ord(c), "02X") for c in word))
# 4D 61 79 61

This prints code points. For the English letters shown here, those match UTF-8 bytes. Do not assume the same relationship holds for every Unicode character.

JavaScript: codePointAt() and fromCodePoint()

The equivalent single-character lookup in JavaScript is:

const letter = "R";
const value = letter.codePointAt(0);
console.log(value); // 82
console.log(value.toString(16).toUpperCase()); // 52
console.log(String.fromCodePoint(parseInt("52", 16))); // R

Both examples show a letter's numeric code, not an alphabet position. Use a text encoder when you need the actual encoded bytes of non-ASCII input.

Where the English Letter Chart Stops Working

This chart covers ASCII, not every writing system. Letters such as é, Arabic characters, and many other symbols fall outside its 128-code range.

For é, the Unicode code point is U+00E9. Its UTF-8 bytes are C3 A9. The single byte E9 represents it in Latin-1, but that byte alone is not a valid UTF-8 encoding of the character.

Even English letters can use different bytes under another character encoding. In the EBCDIC mappings documented by IBM, uppercase A is C1, while ASCII uses 41. A table labeled only “letter codes” leaves out information you need to decode reliably.

For modern UTF-8 text, the ASCII English letter values in this article remain unchanged. For older files, device protocols, or mainframe data, check the specified encoding before applying the chart. A valid hex string does not establish which character set the bytes came from.

Frequent Lookup Errors and How to Avoid Them

The most common mistakes come from choosing the wrong interpretation rather than doing difficult arithmetic.

Using alphabet positions. A=1 and Z=26 describe a positional system, often called A1Z26. They do not give ASCII values. Converting the number 1 to hex does not produce the encoded text character A.

Counting every value between uppercase and lowercase letters as a letter. After Z at 5A, ASCII includes punctuation before lowercase a at 61. The two letter ranges are separate. A check covering everything from 41 through 7A will also accept some nonletters.

Accepting incomplete byte pairs. A continuous ASCII hex string should have two digits per byte. An odd number of digits usually means a digit is missing or the input follows a different notation. Recover the intended format rather than inserting a guessed zero.

Confusing a hex dump's address with its contents. Many viewers show an offset column, a byte column, and a readable-text column. Only the byte column contains the values you should decode as the file's data.

Before converting, identify the input's encoding, number base, and grouping. Those three checks prevent most avoidable errors.

Questions About Alphabet Hex Codes

What is the hex value of A?

Uppercase A has ASCII hexadecimal value 41, equivalent to decimal 65. Lowercase a has value 61, equivalent to decimal 97. If you mean A as a digit within a hexadecimal number, its numeric value is 10. Specify whether you mean a text character or a hex digit.

What are the hex values of Z and z?

Uppercase Z is ASCII hex 5A, while lowercase z is 7A. Their decimal values are 90 and 122. They mark the ends of the uppercase and lowercase English letter ranges. Hex values after those endpoints do not simply continue into more letters of the English alphabet.

Why does hexadecimal use only A through F?

Base 16 needs 16 digit symbols. The ten familiar digits 0–9 supply the first ten, and A–F supply six more. The next value after F is written 10, meaning one group of sixteen. Letters such as G are therefore unnecessary as hexadecimal digits.

Is 0x41 the same as U+0041?

They identify the same numeric value, but their labels provide different context. 0x41 marks a hexadecimal number. U+0041 identifies the Unicode code point for uppercase A. In ASCII and UTF-8, that character's byte is also 41. Other encodings can store the same character using different bytes.

Can hex values tell me a letter's alphabet position?

Yes, if you first interpret the code using the correct character set. For an uppercase ASCII letter, subtract decimal 64 from its numeric code. For lowercase, subtract 96. For instance, 0x43 equals 67, and 67 minus 64 gives position 3 for C. Validate that the input is a letter first.

Is converting letters to hex a form of encryption?

No. A standard hex to ASCII lookup is reversible without a secret key. Displaying CODE as 43 4F 44 45 changes its representation but does not protect its contents. Someone who knows the character encoding can recover the original letters. Use encryption when confidentiality is the goal.

Can the chart decode every value in a hex file?

No. A hex file or dump may contain images, compressed data, numeric fields, control bytes, or text in another encoding. This chart only identifies ASCII English letters. A byte sequence that does not spell readable words is not necessarily damaged; it may represent something other than alphabetic text.

Use the Case and Encoding to Choose the Right Value

Keep the hex value alphabet chart tied to its scope: ASCII uppercase and lowercase English letters, with matching byte values in UTF-8. Check the case, read the number in base 16, and preserve every byte when converting a word. If the output looks wrong, confirm the source encoding before replacing any values.