Gparted and Disks utility give me different sizes for my hard drive and its partitions. Is there a reason, for both programs, to list different information or is it an error?
GParted & Terminal output: sudo lsblk -o NAME,FSTYPE,SIZE,MOUNTPOINT,LABEL
dev/sda = 298.1 Gib
/dev/sda3 = 191.40 GiB
/dev/sda4 = 92 GiB
/dev/sda5 = 88.40 GiB
/dev/sda6 = 3.60 GiB
Disks Utility output
dev/sdb = 320 Gib
/dev/sda3 = 206 GiB
/dev/sda4 = 99 GiB
/dev/sda5 = 95 GiB
/dev/sda6 = 3.9 GiB
The result shown by sudo lsblk -o NAME,FSTYPE,SIZE,MOUNTPOINT,LABEL performs calculations using the binary prefix i.e. multiples of 1024 (which is 210). So 500107862016 bytes would be equal to 465.76 GB or approximately 466 GB. (You can use -b switch to print in bytes instead of human readable as sudo lsblk -b -o NAME,FSTYPE,SIZE,MOUNTPOINT,LABEL.)
Calculation:
500107862016 bytes = (500107862016 / (1024 ^ 3)) GB = 465.76 GB
While Disks Utility uses decimal prefix for calculation so expressed as multiples of 1000. So 500107862016 bytes here would mean 500.11 GB or 500 GB approx.
Calculation:
500107862016 bytes = (500107862016 / (1000 ^ 3)) GB = 500.11 GB
Just a guess but I would assume that the terminal command is giving you the actual size of a partition, while gparted is giving you the size available using the current allocation size settings. When you format a partition the filesystem uses an allocation size (also called cluster size), the larger the size the less storage you get due to inefficient usage, but you can get faster write speeds as a tradeoff when writing large files.
I don't know this for a fact, but I would assume that Disk Utility is telling you the actual size, and Gparted is telling you the functioning size, since the filesystem and partition table take some room. Allocation sizes aren't a factor, because they don't take up space, it's merely a setting.
