Bash can accept '0x' and '0' notation for hexidecimal and octal numbers, so you just have to output the values. Show Sample Output

If you're going to use od, here's how to suppress the labels at the beginning. Also, it doesn't output the \x, hence the sed command at the end. Remove it for space separated hex values instead Show Sample Output

To do hex to binary: echo 'ibase=16; obase=2; 16*16' | bc # prints: 111100100 To do 16*16 from decimal to hex: echo 'ibase=10; obase=16; 16*16' | bc # prints: 100 You get the idea... Alternatively, run bc in interactive mode (see man page) Show Sample Output

just a bit simpler

Use the standard calculator bc to convert decimals to hex Show Sample Output

Replace (as opposed to insert) hex opcodes, data, breakpoints, etc. without opening a hex editor. HEXBYTES contains the hex you want to inject in ascii form (e.g. 31c0) OFFSET is the hex offset (e.g. 49cf) into the binary FILE

Converts IP octets to hex using printf command. Useful for generating pxeboot aliases in the pxelinux.cfg folder. Show Sample Output

You can use "decode()" in a similar manner: python -c 'print "68656c6c6f".decode("hex")' Show Sample Output

Converts the ascii text to hex from bash. Check the sample output. Show Sample Output

Here's a version that uses perl. If you'd like a trailing newline: perl -pe 's/(.)/sprintf("\\x%x", ord($1))/eg; END {print "\n"}'

Even adds a newline.

Use it to send raw data to a networked device. Used to interact with relay controller board whose documentation is lost, so use wireshark to sniff the sent data and replayed using the command.

Same as another one I saw, just with a cleaner sed command Edit: updated the sed command to use the [[:xdigit:]] character class - more portable between locales Note that it will have a newline inserted after every 32 characters of input, due to the output of xxd Show Sample Output

Just use "od" and it can also dump in decimal or octal. (use -t x1 and not just -x or it confuses the byte order) There is a load of other formatting options, I'm not sure if you can turn off the address at the start of the line. Show Sample Output

Python is always such much more readable than most shell scripting. Show Sample Output

hexdump could be used for conversion too!

Prints a string as a sequence of hexadecimal values. Output comes in space separated pairs, regardless of ASCII or Unicode characters Show Sample Output

Use this function with bash version 4+ to convert arbitrary hexadecimal sequences to binary. If you don't have bash 4+ then modify the lowercase to uppercase demangling statement s=${@^^} to set s equal to the uppercase hex input or the bc command throws an input parser error. Show Sample Output