Hex ↔ ASCII Converter
Understand Hex ↔ ASCII Converter
This converter shows the raw bytes behind a piece of text in hexadecimal, and turns a list of hex bytes back into readable text.
How it works
Text is encoded as UTF-8 first, then each byte is printed as two hex digits: H is 48, e is 65. The unit is a byte and not a character, so anything outside ASCII takes more than one pair — é is C3 A9 and 🌍 is F0 9F 8C 8D — which is exactly how you tell a single-byte encoding problem from a multi-byte one. Going the other way, the input is split on spaces or commas and each piece is parsed as one byte, so anything above FF is rejected.
When to use it
- Checking whether a string is really UTF-8 or has been through a Latin-1 round trip.
- Reading hex bytes copied out of a packet capture, a serial log, or a hex dump.
- Hunting an invisible character — a byte-order mark (EF BB BF) or a non-breaking space (C2 A0) — that is breaking a parser.
- Writing a byte-level test fixture by hand.
Watch out for
- Separators are optional but ambiguity is not. 48 65 6C, 48,65,6C and the continuous 48656C all decode, and 0x prefixes are stripped — but a continuous run with an odd number of digits is rejected rather than guessed at, because padding it at either end gives a different answer.
- Byte count is not character count. Ten emoji are 40 bytes, which is why a column sized in characters and one sized in bytes disagree about whether a value fits.
- Decoding assumes the bytes are text. Hex taken from a binary file comes back as replacement characters, not as a file.
Frequently Asked Questions
How to convert hex to ASCII?
Paste hex bytes (e.g., 48 65 6C 6C 6F) into the input. Each two-digit hex pair maps to one ASCII character: 0x48 = 72 = "H", 0x65 = 101 = "e". The tool auto-detects space-separated, comma-separated, 0x-prefixed, and continuous hex formats and outputs the UTF-8 text.
What separators are supported?
Four input formats are accepted when decoding: space-separated (48 65 6C), comma-separated (48,65,6C), 0x-prefixed (0x48 0x65 0x6C), and continuous with no separator (48656C). The format is detected automatically. When encoding, you pick the separator placed between output bytes, defaulting to a single space.
Is hex encoding the same as hex dump?
A hex dump shows the raw hex bytes of binary data, often with offsets and ASCII sidebar. This tool is simpler: it converts the UTF-8 bytes of a text string to hex and back — ideal for debugging string encoding issues.
How to Use Hex ↔ ASCII Converter
- Paste or type your input in the input area above.
- The tool processes your input automatically or click Run.
- Copy or download the result using the action buttons.
- Use Ctrl+Enter to run quickly from the keyboard.