How to find the right memory size?

We have a Linux machine with 32G. We capture the mem as follows: mem= cat /proc/meminfo | grep MemTotal | awk '{print $2}' echo $mem 32767184 and now we convert it to GIGA: mem_in_giga= echo $(( $mem / 1024 / 1024)) echo $mem_in_giga 31 but from the results we get 31 and not 32G. The same story with the free command: free -g total used free shared buff/cache available Mem: 31 9 17 0 4 20 Swap: 7 0 7 So how do we get "32G" from any command?