Hex Decoder

Use this hex decoder for byte dumps, protocol payloads, file headers, and escaped data. It accepts common hex formats and makes control characters such as 0A and 0D easier to identify.

What is Hexadecimal?

Hexadecimal (base-16) is a number system that uses 16 symbols: digits 0–9 and letters A–F. It's the standard way to represent binary data in a human-readable format because each hex digit maps exactly to 4 bits, making it compact and easy to convert mentally.

Every time you look at a hex dump, a network packet, or a file header, you're seeing data encoded as hex. Converting it to readable ASCII text is one of the most common operations in debugging, data analysis, and reverse engineering.

Hex to ASCII Conversion Method

The conversion from hexadecimal to ASCII is mechanical and reversible:

1. Split the hex string into byte pairs — each pair of hex digits represents one byte (8 bits)
2. Convert each pair to decimal — multiply the first digit by 16, add the second: 4×16 + 8 = 72
3. Look up the ASCII character — decimal 72 = 'H', 101 = 'e', 108 = 'l', 111 = 'o'
4. Combine characters — the result is "Hello"

ASCII vs UTF-8

For values 0x00–0x7F, ASCII and UTF-8 produce identical results — UTF-8 is backward-compatible with ASCII. The difference appears above 0x7F: ASCII can't represent these values, while UTF-8 uses multi-byte sequences to encode over 1 million characters. Toggle between encodings in the format options above. If your decoded text shows up as garbled symbols like café, see our guide on decoding hex to UTF-8 text to fix the encoding mismatch.

Common Use Cases

• Debugging network traffic — reading hex dumps from Wireshark or tcpdump to see the plaintext inside a packet
• Reverse engineering — examining binary file headers and signatures (for example, 89 50 4E 47 begins the standard PNG signature)
• Web development — inspecting byte sequences written as continuous hex, 0x48, or \x48 escapes
• Cryptography — reading hash outputs, keys, and encrypted data that are conventionally printed in hex
• Serial communication — interpreting UART/SPI/I2C data logs from embedded devices and microcontrollers
• Database administration — viewing BLOB and binary column data dumped as hexadecimal

A typical workflow: you capture a payload, copy the hex, and paste it here to confirm what the bytes actually say. For example, the hex 47 45 54 20 2F 20 48 54 54 50 decodes to GET / HTTP — the opening of an HTTP request. If you regularly work with raw byte output, our guide on reading and converting hex dumps walks through xxd, hexdump, and identifying files by their signature. And because hexadecimal also describes colors on the web, the same base-16 you see here powers CSS values like #FF5733 — explained in how hex color codes work.

Decoding Byte Dumps, Payloads, and File Headers

A hex decoder earns its keep when you are staring at raw bytes and need to know what they say. Capture a packet in Wireshark, dump a file with xxd or hexdump, or copy a BLOB column out of a database, and you get hex — paste it above to see the plaintext hiding inside. The decoder normalizes spaced, continuous, colon-separated, and 0x-prefixed input automatically. Copy the hex byte column only; remove address offsets and the printable-text gutter first.

Reading magic bytes

The first bytes of a file identify its format more reliably than the extension does. Decode the first line of a dump and compare: 89 50 4E 47 marks a PNG, 25 50 44 46 decodes to %PDF, 50 4B 03 04 is a ZIP archive (also DOCX and JAR), and 7F 45 4C 46 is an ELF executable. Our walkthrough on reading and converting hex dumps covers offsets, the ASCII gutter, and a longer signature table.

Spotting control characters

Decoded payloads are full of bytes that do not print: 0A (line feed), 0D (carriage return), 09 (tab), and 00 (null). Use the non-printable option above to render them as escapes such as \x0A or Unicode code points so delimiters and terminators in a protocol stream stay visible instead of vanishing into whitespace.