MEASUREMENT GUIDE
Decimal vs binary data units
Digital storage and network speeds use two different prefix systems. Confusing them can produce noticeably different results, especially for large files and storage devices.
Decimal units (base 1,000)
The SI prefixes kilo, mega, giga and tera represent powers of 1,000. For example, 1 kB is 1,000 bytes, 1 MB is 1,000,000 bytes and 1 GB is 1,000,000,000 bytes.
Binary units (base 1,024)
IEC binary prefixes are kibi, mebi, gibi and tebi. Thus, 1 KiB is 1,024 bytes, 1 MiB is 1,048,576 bytes and 1 GiB is 1,073,741,824 bytes.
Bits and bytes
One byte is eight bits. The symbol b represents a bit and B represents a byte. Therefore, 100 Mbit/s is equivalent to 12.5 MB/s before accounting for protocol overhead and other limitations.
| Decimal | Bytes | Binary | Bytes |
|---|---|---|---|
| 1 kB | 1,000 | 1 KiB | 1,024 |
| 1 MB | 1,000,000 | 1 MiB | 1,048,576 |
| 1 GB | 1,000,000,000 | 1 GiB | 1,073,741,824 |
| 1 TB | 1,000,000,000,000 | 1 TiB | 1,099,511,627,776 |