What is the difference between ASCII and UTF-8 in hexadecimal conversion?

Standard ASCII uses 1 byte (2 hex digits, 00 to 7F) per character and only covers basic English letters, digits, and punctuation. UTF-8 is backward-compatible with ASCII for bytes 00–7F, but uses 2 to 4 bytes (4 to 8 hex digits) to encode international characters, accented letters (like é = C3 A9), and emojis (like 🚀 = F0 9F 9A 80).

Why does an emoji produce 4 bytes (8 hex digits) in UTF-8?

Emojis reside in the Supplementary Planes of Unicode (code points above U+FFFF). In UTF-8 encoding, any code point from U+10000 to U+10FFFF is encoded as a 4-byte sequence starting with byte F0–F4.

Can I decode hex strings that contain 0x, \x, commas, or spaces?

Yes! As long as 'Ignore whitespace, prefixes & separators' is checked (enabled by default), you can paste hex formatted with spaces, commas, colons, 0x prefixes, \x escapes, URL % signs, or HTML &#x...; entities, and the decoder will strip them automatically.

Online Text to Hexadecimal & Hex to Text Converter

Instantly convert plain text and UTF-8 strings (including international characters and emojis) into hexadecimal representation, or decode hex bytes back into human-readable text. Featuring 9 developer output formats (space-separated, 0x arrays, \x string escapes, URL percent-encoding, HTML hex entities, and CSS escapes) plus a live 16-byte Hex Dump inspector.

Source Input

Characters: 0

Bytes: 0

Result

Hex Dump / Byte Inspector (16 Bytes per Row)

Enter text or hexadecimal data above to inspect byte offsets.

Conversion Mode

Text → Hexadecimal (Encode)

Hexadecimal → Text (Decode)

Format & Encoding Options

Character Encoding:

Hex Output Format:

Uppercase hex digits (A–F)

Strict hex & UTF-8 validation

Ignore whitespace, prefixes (0x, \x, %) & separators

Show 16-byte Hex Dump Inspector

How to Convert Text to Hexadecimal (and Hex to Text)

Select Conversion Direction – Choose Text → Hexadecimal to encode strings into hex bytes, or Hexadecimal → Text to decode hex values back into readable characters.
Enter Your Data – Type or paste your input into the Source Input box on the left, or click Sample Text / Sample Hex to test immediately.
Configure Encoding & Format – Select UTF-8 (recommended for modern text and emojis) or ASCII, and choose from 9 output formats including 0x C arrays, \x escapes, URL % encoding, or HTML entities.
Inspect & Export – View byte offsets in the Hex Dump Inspector and click Copy to Clipboard or Download .txt.

Understanding ASCII vs. UTF-8 Hexadecimal Encoding

In computing, every byte of data consists of 8 bits, which can hold a value from 0 to 255 in decimal—or 00 to FF in base-16 hexadecimal (where each hex digit represents exactly 4 bits, or one "nibble").

While basic English characters take only 1 byte in both ASCII and UTF-8, international characters and emojis require between 2 and 4 bytes in UTF-8:

Character	Unicode Code Point	UTF-8 Hex Bytes	Byte Count	HTML Hex Entity
`A` (Latin Capital A)	`U+0041`	`41`	1 byte	`A`
`é` (Latin Small E with Acute)	`U+00E9`	`C3 A9`	2 bytes	`é`
`€` (Euro Sign)	`U+20AC`	`E2 82 AC`	3 bytes	`€`
`🚀` (Rocket Emoji)	`U+1F680`	`F0 9F 9A 80`	4 bytes	`🚀`

Quick ASCII-to-Hex Reference Table

Character Group	ASCII Characters	Decimal Range	Hexadecimal Range
Line Feed (LF) / Newline	`\n`	`10`	`0A`
Carriage Return (CR)	`\r`	`13`	`0D`
Space	(space)	`32`	`20`
Digits (0–9)	`0` through `9`	`48` – `57`	`30` – `39`
Uppercase Letters (A–Z)	`A` through `Z`	`65` – `90`	`41` – `5A`
Lowercase Letters (a–z)	`a` through `z`	`97` – `122`	`61` – `7A`

Frequently Asked Questions

How do I convert a hex string with "0x" or "\x" prefixes back to text?

Select Hexadecimal → Text (Decode) in the settings panel and paste your hex string into the input box. With Ignore whitespace, prefixes & separators checked, prefixes like 0x, \x, %, and commas are stripped automatically before decoding.

Why do HTML Hex Entities (é) look different from UTF-8 bytes (C3 A9)?

HTML numeric character references (&#x...;) and CSS escapes (\00E9) represent the character's Unicode code point (U+00E9 for é), whereas standard hex encoding represents the UTF-8 byte sequence (C3 A9) stored in memory. Our converter handles both accurately so your HTML entities never render as garbled text.

What do the dots (.) mean in the right column of the Hex Dump Inspector?

In standard hex dump utilities (such as xxd or hexdump -C), the right-hand ASCII column displays printable ASCII characters (bytes 20 to 7E) directly and substitutes non-printable control characters (like newline 0A) or multi-byte UTF-8 continuation bytes with a period (.) so the column alignment remains intact.