Why a gigabyte is two sizes, and your drive looks smaller.
Why a 1 TB drive shows as about 931 GB, how MB and GB are counted by 1,000 and by 1,024, and how to convert between them.
By Suraj Kumar3 min read
Kilo, mega and giga mean 1,000, a million and a billion. Computers count in powers of two, so two ways of counting grew up side by side.
By 1,000 and by 1,024.
Drive makers, and Apple's systems since 2009, count 1,000 bytes to a kilobyte and 1,000 MB to a GB. Windows counts 1,024 to each step and still writes KB, MB and GB. The 1,024-based units have their own names, KiB, MiB and GiB, which the converter uses.
Why a 1 TB drive shows 931 GB.
1 TB is a million million bytes. Divided by 1,024 three times it is about 931.323, which Windows shows as 931 GB. Nothing is missing; it is counted another way. The converter gives both counts with every answer.
Bits and bytes.
Internet speeds are given in bits a second, and there are 8 bits in a byte. 100 Mbit is 12.5 MB, so a 100 Mbps line moves about 12.5 MB a second at best.
Further reading
Topics: mb to gb · gb to mb · 1000 or 1024 · gb vs gib · why is my drive smaller · file size converter
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