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Bytes Converter

Bytes, kilobytes, megabytes, gigabytes, terabytes.

Decimal (1000-based)
B1,000,000,000
KB1,000,000
MB1,000
GB1
TB0.001
PB1.000e-6
Binary (1024-based)
B1,000,000,000
KiB976,562.5
MiB953.674316
GiB0.931323
TiB9.095e-4
PiB8.882e-7

Hard drives use decimal (1 GB = 1,000,000,000 bytes). Operating systems often use binary (1 GiB = 1,073,741,824 bytes). That is why your “1 TB” drive shows as 931 GB.

About

Type any value and unit. See the same value in every common storage unit, both decimal (1 KB = 1,000 B) and binary (1 KiB = 1,024 B). Both conventions are used in the wild and they disagree by a few percent at GB scale.

How to use

  1. Type a value.
  2. Pick the source unit.
  3. Read every unit on both scales.

FAQ

Why do my hard drive's stated size and Windows disagree?+

Drive manufacturers use decimal (1 TB = 10^12 bytes). Windows reports binary (1 TiB = 2^40 bytes). A '1 TB' drive shows as 931 GiB. Same bytes, different label.

Which one is 'correct'?+

Both are. The IEC standardized binary suffixes (KiB, MiB, GiB) in 1998, but most software still says 'GB' when it means 'GiB'. Treat the difference as a 7% rule of thumb at TB scale.