Byte/Bits Unit Conversion

Terabyte (TB): Originally 1,099,511,627,776 (240) bytes, although communications and secondary storage systems developers started using the term to mean 1,000,000,000,000 (10¹²) bytes. To reduce confusion, we now use the term tebibyte (TiB) for 2⁴⁰ bytes, defining terabyte (TB) to mean 10¹² bytes. The figure below shows the full range of decimal and binary values and names.

Decimal	Abbreviation	Value	Binary term	Abbreviation	Value	% Larger
kilobyte	KB	10001	kibibyte	KiB	210	2%
megabyte	MB	10002	mebibyte	MiB	220	5%
gigabyte	GB	10003	gibibyte	GiB	230	7%
terabyte	TB	10004	tebibyte	TiB	240	10%
petabyte	PB	10005	pebibyte	PiB	250	13%
exabyte	EB	10006	exbibyte	EiB	260	15%
zettabyte	ZB	10007	zebibyte	ZiB	270	18%
yottabyte	YB	10008	yobibyte	YiB	280	21%
ronnabyte	RB	10009	robibyte	RiB	290	24%

And,

1 byte = 8bits

For example:

What is the actual number that would show up on your computer when the hard drive manufacturer labeled it as 18TB?

18 * 10¹² = 18,000,000,000,000 bytes

18,000,000,000,000 bytes / 2⁴⁰ = 16.37 TiB

So, the system would show 16.37 TiB actual size.