xxd

Create a hex dump of a file

$ xxd [file]

$ xxd -p [file]

$ xxd -b [file]

$ xxd -l [16] [file]

$ xxd -s [0x100] [file]

$ xxd -i [file]

$ xxd -r [hexdump.txt] [output.bin]

$ echo "[48656c6c6f]" | xxd -r -p

xxd [options] [infile [outfile]]

xxd creates a hexadecimal dump of a file or standard input. The output shows the offset, hexadecimal values, and ASCII representation of the data. It can also reverse a hex dump back to the original binary.
The default output format shows 16 bytes per line with the file offset, hex values in groups of 2 bytes, and printable ASCII characters. The -p option produces a continuous hex string without formatting.
The -i option generates C source code with the data as an unsigned char array, useful for embedding binary data in programs.
The -r option reverses the process, converting a hex dump back to binary. Combined with -p, it can convert plain hex strings to binary data.

-b

Binary digit dump instead of hexadecimal

Format output with specified columns per line (default: 16)

Number of bytes per group (default: 2)

Output as C include file (array definition)

Stop after outputting len bytes

Plain hexdump style (continuous hex without addresses)

Reverse operation: convert hexdump to binary

Start at specified offset in file

Use uppercase hexadecimal letters

Little-endian dump (group bytes are reversed)

xxd integrates with vim for hex editing. In vim, use :%!xxd to convert buffer to hex dump, edit the hex values, then :%!xxd -r to convert back to binary.

When using -r, xxd is tolerant of missing or out-of-order lines if the output is seekable. Non-hex characters in the hex column are ignored during revert. The -r option requires properly formatted input matching xxd's output format (or plain hex with -p).

xxd was written by Juergen Weigert and is distributed with vim. It was created as a more versatile alternative to traditional hex dump utilities like od. The tool has been part of the vim distribution since the mid-1990s and is commonly available on Unix-like systems.

od(1), hexdump(1), hd(1), vim(1)