Formula
value in target unit = value × (bytes per source unit) ÷ (bytes per target unit)
- 1 KB = 1,000 B, 1 MB = 1,000,000 B, 1 GB = 10⁹ B, 1 TB = 10¹² B
- 1 KiB = 1,024 B, 1 MiB = 1,024² B, 1 GiB = 1,024³ B, 1 TiB = 1,024⁴ B
- 1 byte = 8 bits
Convert to bytes, then to the unit you want.
Worked example
1 TB in GiB
- Value
- 1
- From
- Terabyte (TB)
- To
- Gibibyte (GiB)
Terabyte to Gibibyte
931.322574615 GiB
In words: 1 TB = 931.322574615 GiB
How it works
Two systems share the same letters. Storage makers and networks use decimal prefixes, where 1 GB is exactly 1,000,000,000 bytes. Operating systems have often shown capacity with binary multiples, where one gibibyte (GiB) is 1,024³ = 1,073,741,824 bytes, sometimes still labelling it "GB". That is why a 1 TB drive (10¹² bytes) appears as about 931 GiB — nothing is missing, the unit is simply larger.
The IEC names KiB, MiB, GiB and TiB were introduced to remove the ambiguity, and both families are listed here by name. A byte is 8 bits, and network speeds are quoted in bits per second, so a 100 Mbps connection moves at most 12.5 MB of data per second. For transfer times see Speed Converter; for any other unit use the Unit Converter.
Assumptions and limits
- Decimal (SI) prefixes use powers of 1,000 and binary (IEC) prefixes use powers of 1,024.
- Petabytes and larger units are not included.