data · GB
Gigabyte (GB)
A gigabyte (GB) in the SI (decimal) system is 10⁹ bytes = 1,000,000,000 bytes. Operating systems may also show gibibytes (GiB = 2³⁰ bytes).
Definition
A gigabyte (GB) in the SI (decimal) system is 10⁹ bytes = 1,000,000,000 bytes. Operating systems may also show gibibytes (GiB = 2³⁰ bytes).
History & origin
SI prefixes (kilo, mega, giga) are powers of 10. IEC binary prefixes (kibi, mebi, gibi) are powers of 2 — important for storage marketing vs. OS reporting.
Conversion formula
MB = GB × 1000 · GiB = GB × (10⁹ / 2³⁰) ≈ GB × 0.931323 · TB = GB ÷ 1000
Frequently asked questions
- Why does a 1 TB drive show ~931 GB?
- Vendors use SI GB/TB (powers of 10); many OS report binary GiB. 1,000,000,000,000 bytes ≈ 931 GiB.
- Is GB the same as GiB?
- No. 1 GB = 10⁹ bytes; 1 GiB = 2³⁰ bytes (about 1.074 GB).
- How many MB in 1 GB?
- 1000 MB (SI) or 1024 MiB if using binary megabytes.
Related units
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