Unit Conversion

Convert numbers between two units quickly and precisely

Data Size Converter

Unit Conversion

Convert data sizes: byte, kilobyte, and kibibyte

Digital data sizes are stated in byte (B), with bit (bit) as the smallest unit (1 byte = 8 bit). For larger amounts, there are two parallel prefix systems: the decimal SI prefixes (KB, MB, GB – base 1000), as used by hard drive manufacturers, and the binary IEC prefixes (KiB, MiB, GiB – base 1024), as often shown by operating systems. This mix-up is why a "1 TB" drive shows up as less than 1,000 GB in File Explorer or Finder.

Key conversion factors:

  • 1 byte (B) = 8 bit
  • 1 kilobyte (KB) = 1,000 byte (decimal) ≠ 1 kibibyte (KiB) = 1,024 byte (binary)
  • 1 gigabyte (GB) = 1,000³ byte (decimal) ≠ 1 gibibyte (GiB) = 1,024³ byte (binary)
  • 1 GiB ≈ 1.074 GB – the difference grows with the order of magnitude

Applications:

  • IT & storage technology: converting between manufacturer specs (decimal) and OS display (binary)
  • Networking: converting data rates and transfer volumes
  • Software development: exact memory and file size calculations

The data size converter clears up the difference between decimal and binary prefixes for storage and transfer figures.

Frequently asked questions about converting data size

Gigabyte (GB) follows the decimal definition (1 GB = 1,000³ byte), as used by hard drive manufacturers. Gibibyte (GiB) follows the binary definition (1 GiB = 1,024³ byte), as often shown by operating systems. 1 GiB equals about 1.074 GB – which is why a "1 TB" drive shows up as less than 1,000 GB in File Explorer.

1 byte equals 8 bit. A bit is the smallest unit of data and can only be 0 or 1; a byte combines 8 such bits and can therefore represent 256 different values.

Hard drive manufacturers calculate decimally (1 TB = 1,000 GB), but operating systems usually display storage in binary units (TiB, GiB, MiB). Since 1 GiB is larger than 1 GB, a "1 TB" drive appears smaller in File Explorer or Finder, even though it's exactly the same amount of data.