Gibibyte (GiB)

Definition

One binary gigabyte, 1024³ bytes (2³⁰ B) — what an OS often labels "GB".

History

The gibibyte was defined by the IEC in 1998 as the binary counterpart to the gigabyte, exactly 1024 to the third power bytes. It was introduced to end the confusion between decimal and binary sizes.

Where it is used

The gibibyte is what an operating system often shows when it labels a drive GB, which is why a 1 terabyte drive appears as about 931 gibibytes.

Typical uses include reported drive capacity, RAM.

Conversion pages

These pages convert gibibyte to or from another unit in digital storage.

No conversion pages use this unit yet.

Other Digital storage units

• Byte (B)
• Bit (bit)
• Kilobyte (kB)
• Megabyte (MB)
• Gigabyte (GB)
• Terabyte (TB)
• Mebibyte (MiB)
• Tebibyte (TiB)

Sources

• IEC 80000-13 IEC 80000-13 (quantities and units — information science); NIST on binary prefixes · Dataset reviewed Nov 11, 2026