Convert from hexadecimal to decimal and vice versa from the command line

To convert from hexadecimal to decimal $ echo "ibase=16; 7FF" | bc 2047 Remember: ibase, input ‘i’ base. $ echo $((16#2A)) 42 To convert from decimal to hexadecimal $ printf '%x' 42 2a and: $ echo "obase=16; 10" | bc Remember: obase, output ‘o’ base.