Why does my 1 TB drive only show 931 GB?

Because the manufacturer counts a terabyte as 1,000,000,000,000 bytes (decimal) while your operating system divides by 1,073,741,824 and labels the result GB. 1,000,000,000,000 ÷ 1,073,741,824 = 931 GiB. No capacity is missing — the two systems simply use different definitions.

What is the difference between MB and MiB?

MB is decimal: 1,000,000 bytes. MiB (mebibyte) is binary: 1,048,576 bytes, or 1,024 × 1,024. The IEC introduced the "bi" names in 1998 to end the ambiguity, but Windows and many apps still print MiB values with an MB label.

How many megabytes are in a gigabyte?

Decimal: 1,000 MB in 1 GB. Binary: 1,024 MiB in 1 GiB. Most storage marketing uses the decimal figure, which is why a "1 GB" file and a "1 GiB" file differ by about 74 MB.

What is the difference between a bit and a byte?

A byte is 8 bits. Bits are used for data transfer rates (Mbps) and bytes for file sizes (MB). A 100 Mbps connection therefore downloads at about 12.5 MB/s — the factor of 8 accounts for most apparent speed shortfalls.

How long does it take to transfer 1 TB?

Divide the size by the transfer rate, remembering that rates are quoted in bits. On a 1 Gbps connection, 1 TB takes roughly 2 hours 13 minutes at theoretical maximum: 8,000,000,000,000 bits ÷ 1,000,000,000 bps ≈ 8,000 seconds. Real-world overhead usually adds 10–20%.

Data Storage Converter

Storage is the one unit system where two definitions compete: drive makers use decimal (1 GB = 1,000,000,000 bytes) while operating systems use binary (1 GiB = 1,073,741,824 bytes). This converter shows both, so a "1 TB" drive reporting 931 GB stops being a mystery.

Value

Convert from

—

Unit	Value