Standard IEC prefixes and descriptions for binary multiples were introduced in 1998/99 but are still widely misused.
Prefixes MB, GB, TB, PB, ...
Descriptive terms (mega, giga, tera, peta, exa - bytes).
Prefixes MiB, GiB,TiB, PiB, EiB, ZiB,YiB
Descriptive terms (mebi, gibi, tebi, pebi, exbi - bytes).
Decimal Disk drives, DVD capacity |
Power of 2 (binary) RAM, CD capacity |
---|---|
KB 1000 bytes | KiB = 2^10 =1,024 bytes |
MB 1000^2 = 1000,000 bytes | MiB = 2^20 = 1024^2 =1,048,576 bytes |
GB 1000^3 =1000,000,000 bytes | GiB = 2^30 = 1024^3 =1,073,741,824 bytes |
TB: 1000^4 =1000,000,000,000 | TiB = 2^40 = 1024^4 =1,099,511,627,776 bytes |
PB: 1000^5 =1000,000,000,000,000 | PiB = 2^50 = 1024^5 |
EB: 1000^6 =1000,000,000,000,000,000 | EiB = 2^60 = 1024^6 |
ZB: 1000^7 | ZiB = 2^70 = 1024^7 |
YB: 1000^8 | YiB = 2^80 = 1024^8 |
Any of the above can be entered directly into a spreadsheet e.g. =1024^3 will give 1 GiB
In PowerShell you can enter units with the decimal shortcut notation 1MB, 1GB, 1TB, 1PB etc, however this will incorrectly expand to a Power of 2 value: 1024, 1048576 etc.
Hard drive manufacturers market disk drives in decimal (base 10) capacity GB.
Network speeds
A 100 megabit network has a capacity of 100,000,000 bits per second.
Data Transfer packets are normally 64 KB = 65,536 Bytes or 524,288 bits (bits = Bytes x 8 )
So in this example the network would transfer around 200 packets per second.
“Failure of the NASA Mars Climate Orbiter occurred because the flight system software was written using metric units, while the ground crew were entering course correction and thruster data using Imperial measures”
Related
Convert bytes / KB/ MB / KiB / MiB / GB / GiB
The bash utility units can convert e.g. units -t '500GB' 'GiB'