TAHA Engineering Toolsby TAHA Knowledge Lab

Computer & IT

Bits, Bytes & Storage Unit Converter

Convert bits and bytes between decimal (KB, MB, GB) and binary (KiB, MiB, GiB) units.

Inputs

Decimal units (kB, MB, GB, TB) use powers of 1000; binary units (KiB, MiB, GiB, TiB) use powers of 1024.

Result

Converted value
931.322574615
Exact number of bytes
1,000,000,000,000 bytes
In decimal (SI) units — powers of 1000
1 × 10¹² B 1,000,000,000 kB 1,000,000 MB 1,000 GB 1 TB 0.001 PB
In binary (IEC) units — powers of 1024
1 × 10¹² B 976,562,500 KiB 953,674.316406 MiB 931.322574615 GiB 0.909494701773 TiB 0.00088817842 PiB
In bits
8 × 10¹² bit = 8,000,000 Mbit = 7,629,394.53125 Mibit

1 TB = 931.322574615 GiB (1,000,000,000,000 bytes).

Educational estimate — check the assumptions below.

About this calculator

Computer storage is counted in bytes (8 bits each), but there are two ways of counting large amounts. Drive and network makers use decimal prefixes — 1 kB = 1000 bytes, 1 GB = 1,000,000,000 bytes. Memory and many operating systems count in powers of 1024, which the IEC standard names binary prefixes — 1 KiB = 1024 bytes, 1 GiB = 1,073,741,824 bytes. Mixing the two is why a new “1 TB” drive appears as about “931 GB” on a computer that really means GiB.

Formula

Decimal units (kB, MB, GB, TB) step up by 1000. Binary units (KiB, MiB, GiB, TiB) step up by 1024. The “i” in the name tells you it is a binary unit.

1 byte = 8 bits    1 kB = 103 B    1 MB = 106 B    1 GB = 109 B    1 TB = 1012 B

1 KiB = 210 B = 1024 B    1 MiB = 220 B    1 GiB = 230 B    1 TiB = 240 B

Decimal and binary storage units compared
Decimal (× 1000)Binary (× 1024)Binary is larger by
1 kB
1,000 bytes		1 KiB
1,024 bytes		2.4%
1 MB
1,000,000 bytes		1 MiB
1,048,576 bytes		4.86%
1 GB
1,000,000,000 bytes		1 GiB
1,073,741,824 bytes		7.37%
1 TB
1,000,000,000,000 bytes		1 TiB
1,099,511,627,776 bytes		9.95%

Inside each system the steps are whole numbers: 1 GB = 1000 MB and 1 GiB = exactly 1024 MiB. Between the two systems they are not: 1 GB = about 953.6743 MiB.

Worked example

1 GB to MiB (decimal to binary):

  • 1 GB = 1,000,000,000 bytes
  • 1 MiB = 1024 × 1024 = 1,048,576 bytes
  • 1,000,000,000 ÷ 1,048,576 = 953.67431640625 MiB ≈ 953.6743 MiB

1 GiB to MiB (binary to binary):

  • 1 GiB = 1024 × 1024 × 1024 = 1,073,741,824 bytes
  • 1,073,741,824 ÷ 1,048,576 = exactly 1024 MiB

So 1 GiB is 73,741,824 bytes (about 7.4%) more than 1 GB.

More examples:

  • A 1 TB drive = 10¹² bytes = 10¹² ÷ 2⁴⁰ = 0.9095 TiB = 10¹² ÷ 2³⁰ = 931.32 GiB.
  • 16 GiB of RAM = 16 × 1,073,741,824 = 17,179,869,184 bytes = 17.18 GB.
  • 100 Mbit = 100,000,000 ÷ 8 = 12.5 MB.

Assumptions and limitations

  • Unit names follow IEC 80000-13: decimal prefixes (k, M, G, T) are powers of 1000 and binary prefixes (Ki, Mi, Gi, Ti) are powers of 1024.
  • Some software and older documents write “KB”, “MB” or “GB” when they mean 1024-based units. Check which convention a figure uses before comparing.
  • Usable capacity of a drive is lower than its raw size because of formatting, file-system structures and reserved space.

References

  • IEC 80000-13: Quantities and units — Information science and technology (bit, byte, binary prefixes Ki, Mi, Gi, Ti).