Data Size Converter

Convert between bytes, KB, MB, GB and TB — decimal and binary, side by side.

What you provide

Result

1 TB = 1,000,000,000,000 bytes

Decimal units (KB, MB, GB) use powers of 1000 and are how storage is sold; binary units (KiB, MiB, GiB) use powers of 1024 and are how your operating system reports free space. A "1 TB" drive is 1000 GB decimal, which the OS shows as about 931 GiB — same drive, different unit.

Diagnostic telemetry
Bytes
1,000,000,000,000
Decimal (÷1000)How storage is sold
1 TB
Binary (÷1024)How your OS reports it
931.323 GiB
KB / KiB
1,000,000,000 / 976,562,500
MB / MiB
1,000,000 / 953,674.316
GB / GiB
1,000 / 931.323
TB / TiB
1 / 0.9095

What this cannot tell you

  • Pure arithmetic. It converts between units; it does not measure any actual disk or file.
  • Decimal (KB/MB/GB) and binary (KiB/MiB/GiB) are genuinely different units. The tool shows both because manufacturers and operating systems disagree about which to call "GB".

Take this with you

Data Size Converter on RunTheTests — free browser-based calc tools, no sign-up.