How many GB is my RAM Linux?

To see the total amount of physical RAM installed, you can run sudo lshw -c memory which will show you each individual bank of RAM you have installed, as well as the total size for the System Memory. This will likely presented as GiB value, which you can again multiply by 1024 to get the MiB value.

How do I check memory usage in Unix?

To get some quick memory information on a Linux system, you can also use the meminfo command. Looking at the meminfo file, we can see how much memory is installed as well as how much is free.