HesapHanem

GB to GiB Converter

Enter a value and pick a direction to convert between GB and GiB.

How it is calculated

A gigabyte (GB) is the decimal unit, 109 bytes. A gibibyte (GiB) is the binary unit, 230 = 1,073,741,824 bytes. The tool uses one factor, factor = 109 ÷ 230 = 0.931323. GB to GiB is GiB = GB × 0.931323; GiB to GB is GB = GiB ÷ 0.931323. You choose the direction in the selector, and the default is GB to GiB. Results are rounded to four decimals, with the conversion rate shown to six. Negative values are not accepted, and the tool counts only these two units (not TB, MB or bits).

Worked example

A drive sold as 512 GB holds 512 × 109 = 512,000,000,000 bytes. Divide by 1,073,741,824 bytes per GiB, which is the same as multiplying by 0.931323: 512 × 0.931323 = 476.8372 GiB. That is the size an operating system reporting in binary units will show for the drive. The gap of about 35 units is not lost space, only the difference between the two definitions of “giga”.

Try this example →

Common mistakes

  • Converting in the wrong direction. A drive advertised in GB needs GB to GiB to see what a binary-reporting system shows; using GiB to GB makes the number bigger, not smaller (512 becomes 549.7558).
  • Treating GB and GiB as the same because they differ by only a letter. The difference is about 7.4% at the giga level, which is why a 512 GB drive looks like 476.8 GiB.
  • Applying the 0.931323 factor to MB, TB or Mb. The factor belongs to the giga step only, and megabits are bits, not bytes.
  • Expecting formatted capacity to equal the converted figure. The tool converts units only; file system overhead and reserved space come on top and are not included.
  • Blaming the drive maker for “missing” space when the operating system is showing GiB under the GB label. Check which unit the system really uses.

Sources

About this calculator

The confusion between GB and GiB comes down to two different definitions of “giga.” Storage manufacturers and most marketing materials use the decimal definition, 1 GB = 10⁹ bytes (1,000,000,000 bytes), following the SI prefix system. Operating systems and file managers, on the other hand, often report sizes using the binary definition, 1 GiB = 2³⁰ bytes (1,073,741,824 bytes) — which is roughly 7.4% larger than a GB.

That mismatch is exactly why a “1 TB” hard drive shows up as roughly 931 GiB in Windows' file explorer. This converter switches between the two so IT professionals, developers, and anyone puzzled by a drive that looks smaller than advertised can see precisely where the missing space actually went — it isn't missing at all, just measured differently.

Was this helpful?

You can pick up to 3 reactions.

Comments (1)

  • Editorial team

    Windows reports sizes in binary units but labels them GB, so the number in its file explorer is really a GiB figure. macOS and many Linux tools report decimal units instead, which is why the same drive can look different on two computers. For a terabyte-class drive, enter the capacity in GB, for example 1000 for a 1 TB drive, and you get about 931.32 GiB. Which operating system or tool are you comparing against when the numbers disagree?

Popular calculators

Loan Calculator

Monthly payment, total interest and full amortization schedule.

Percentage Calculator

Percent change, percent of, and ratio calculations.

Discount Calculator

Calculate final price, savings, and discount amount.

BMI Calculator

Body mass index from height and weight (metric or imperial).

Age Calculator

Compute your exact age in years, months and days from a birth date.

Compound Interest Calculator

Calculate the final amount and interest earned with compounding.

All Calculators