Is there one line of code that will display free-size and disk-space of your logical disk in gb instead of mb? I tried doing some research but I couldn't find one liner, I did give this an attempt which was to divide it by 1GB, but that didn't work, how can I accomplish this?
gwmi win32_logicaldisk | Format-Table DeviceId, MediaType,Size,FreeSpace /1GB
Try calculated properties. I would also add [math]::Round() to shorten the values:
gwmi win32_logicaldisk | Format-Table DeviceId, MediaType, @{n="Size";e={[math]::Round($_.Size/1GB,2)}},@{n="FreeSpace";e={[math]::Round($_.FreeSpace/1GB,2)}}
n stands for name and e for expression. You could use the full names too, but it's a waste of space if you're writing multiple calculated Properties.