How this instrument works
Every character your computer displays is stored as one or more bytes, and hexadecimal (base 16) is just a compact, human-friendly way of writing those byte values. Each byte (a number from 0 to 255) is written as exactly two hex digits, using 0-9 for the values ten and under and A-F for ten through fifteen — so a byte can range from 00 up to FF. The pair 48 is the byte value 72 in decimal, and 72 happens to be the standard code point for the capital letter H.
Decoding hex to text is a two-step lookup: read each two-digit hex pair as its byte value, then interpret those bytes as UTF-8, the standard encoding that maps byte sequences to Unicode characters. 48 65 6C 6C 6F reads as the five bytes 72, 101, 108, 108, 111, which UTF-8 maps to H, e, l, l, o — spelling "Hello." This instrument accepts hex written either with spaces between each byte pair (48 65 6C 6C 6F) or run together with none at all (48656c6c6f); both forms decode to the identical result, as long as the total number of hex digits is even.
This is strictly the decode direction: hex codes in, text out. If you're starting from text and need the hex codes instead, use this site's Text-to-Hexadecimal Converter, which does exactly the reverse conversion — the two tools are designed as a matched pair so you can check a conversion by running it through the other one and confirming you land back where you started.
- Paste your hex code into the Hex code field, using two digits per byte (0-9 and A-F, upper or lower case both work).
- Spaces between byte pairs are optional — 48 69 and 4869 both decode the same way.
- Read Decoded text for the resulting string.
- Make sure your hex has an even number of digits total; an odd count means a byte pair is incomplete and can't be decoded.
- To go the other direction — text into hex — use this site's Text-to-Hexadecimal Converter instead.
Worked example — decoding 48 69 and 48656c6c6f
Paste 48 69 into the Hex code field. Reading each pair as hex: 48 (hex) = 4x16 + 8 = 72 (decimal), and 69 (hex) = 6x16 + 9 = 105 (decimal). Byte 72 is the letter H and byte 105 is the letter i in UTF-8, so 48 69 decodes to "Hi."
The same encoding works with no spaces at all: 48656c6c6f decodes exactly the same way, just with the byte pairs run together instead of separated. Splitting it back into pairs (48, 65, 6c, 6c, 6f) and converting each from hex gives 72, 101, 108, 108, 111, which UTF-8 maps to H, e, l, l, o — the decoded text reads "Hello."
Punctuation decodes the same as letters. 41 49 21 splits into three bytes: 41 (hex) = 65 = A, 49 (hex) = 73 = I, and 21 (hex) = 33 = the exclamation point. 41 49 21 decodes to "AI!" — proving the conversion isn't limited to letters, since any UTF-8 byte value decodes correctly.
Questions
Does the hex code need spaces between each byte?
No, spaces are optional. This instrument accepts hex either with spaces separating each two-digit byte pair (48 65 6C 6C 6F) or run together with no spaces at all (48656c6c6f) — both decode to the identical result. What matters is that the total number of hex digits is even, since every byte needs exactly two hex digits.
What happens if I paste an odd number of hex digits?
It can't be decoded, because every byte needs exactly two hex digits and an odd-length string leaves one digit without a partner. Double-check you haven't accidentally dropped a leading zero from a byte like 09 (which would leave just a lone 9), since that's the most common cause of an odd-length hex string.
Does upper case or lower case hex matter?
No — 4B and 4b represent the identical byte value and decode identically. Hex digits A through F (or a through f) are just letters standing in for the values 10 through 15, and case has no effect on the number they represent.
How do I convert text into hex codes instead of decoding them?
Use this site's Text-to-Hexadecimal Converter, which does the exact reverse of this tool — you type plain text and it outputs the two-digit hex byte for each character, space-separated. The two tools are a matched pair: encoding a piece of text there and decoding the result here (or vice versa) should always return your original text exactly.
Can this decode hex representing non-English characters or emoji?
Yes, for any character that UTF-8 can represent, which covers the vast majority of world scripts. UTF-8 encodes characters using one to four bytes depending on the character, so a non-English letter or symbol may take more than one hex pair to represent — the decoder handles that automatically as long as you paste the complete multi-byte sequence for that character.