Data Storage Converter
Convert data storage sizes between bytes, KB, MB, GB, TB, and PB. Uses both decimal (1 KB = 1,000 bytes) and binary (1 KiB = 1,024 bytes) standards.
How Data Storage Converter works
Decimal (SI) vs binary (IEC) units
Storage manufacturers use decimal units: 1 KB = 1,000 bytes; 1 MB = 1,000,000 bytes. Operating systems traditionally used binary: 1 KiB = 1,024 bytes. This causes the familiar discrepancy: a "1 TB" hard drive appears as ~931 GB in Windows.
IEC standard
To remove ambiguity, the IEC introduced the kibibyte (KiB), mebibyte (MiB), gibibyte (GiB), and tebibyte (TiB) for binary units. Modern operating systems (macOS, Linux) now use decimal GB consistently; Windows still uses binary GiB but labels them as GB.
Frequently asked questions
Why does my 1 TB drive show as 931 GB?
Drive manufacturers use 1 TB = 1,000,000,000,000 bytes. Windows divides by 1,073,741,824 (1024³) to get GiB, but labels the result as GB. 1,000,000,000,000 ÷ 1,073,741,824 = 931.3 GiB.
How many GB in a TB?
1 TB (decimal) = 1,000 GB. 1 TiB (binary) = 1,024 GiB.
How many MB in a GB?
1 GB (decimal) = 1,000 MB. 1 GiB (binary) = 1,024 MiB.
What is a gigabyte?
A gigabyte (GB) in the decimal system is 1,000,000,000 bytes (10⁹). In the binary system, a gibibyte (GiB) is 1,073,741,824 bytes (2³⁰).
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