Quick Answer: Gigabytes to Gibibytes
One gigabyte equals 0.931322575 gibibytes (1 GB = 0.931322575 GiB).
Conversely, 1 GiB = 1.07374182 GB.
Formula: GiB = GB × 10⁹ ÷ 1024³
Worked examples
- 1 GB = 0.931322575 GiB
- 2 GB = 1.86264515 GiB
- 4 GB = 3.7252903 GiB
Method and limitations
A gigabyte is 1,000,000,000 bytes (SI decimal prefix). A gibibyte is 1024³ = 1,073,741,824 bytes (IEC 80000-13 binary prefix). Convert by taking the decimal byte count and dividing by 1024³, which gives 1 GB = 0.931322575 GiB. This single factor explains every "missing" gigabyte on a new drive: the capacity is decimal, the operating system's display is binary. Calculations use full-precision constants; displayed values are rounded to at most 9 significant figures. Results are rounded for display only. Full precision is kept internally, so long chains of conversions do not accumulate rounding error. Where US customary and imperial units share a name (for example fluid ounces and gallons), this page uses the US customary definition and says so explicitly.
Each factor is exact by definition, derived from exact definitions, or a documented conventional value — see the methodology and sources.
Conversion Formula
A gigabyte is 1,000,000,000 bytes (SI decimal prefix). A gibibyte is 1024³ = 1,073,741,824 bytes (IEC 80000-13 binary prefix). Convert by taking the decimal byte count and dividing by 1024³, which gives 1 GB = 0.931322575 GiB. This single factor explains every "missing" gigabyte on a new drive: the capacity is decimal, the operating system's display is binary.
Complete Guide to Gigabytes to Gibibytes Conversion
What is a Gigabytes?
A gigabyte (GB) is exactly 10⁹ = 1,000,000,000 bytes. G is an SI decimal prefix, so it means a power of 1000 in every other context too (gigawatt, gigajoule, gigahertz).
What is a Gibibytes?
A gibibyte (GiB) is exactly 1024³ = 1,073,741,824 bytes. Gi is a binary prefix standardised in IEC 80000-13 specifically so that powers of 1024 no longer need to borrow SI names.
How the Conversion Works
Multiply gigabytes by 10⁹ to get bytes, then divide by 1024³. The result, 0.931322574615478515625, is exact in binary floating point because both factors are exact.
Why This Conversion Matters
Nearly every reported "missing storage" complaint is this conversion. It also matters commercially: buying 1000 GB of cloud block storage and assuming 1000 GiB leaves you 7.4% short.
Scientific Context
IEC 80000-13:2008 defines Ki, Mi, Gi, Ti, Pi and Ei. The BIPM SI Brochure (9th ed.) defines k, M, G, T as powers of 1000 and explicitly notes they must not be used for powers of two.
Step-by-Step Conversion Guide
Follow these steps to convert gigabytes to gibibytes manually:
Start with your value in gigabytes
Example: You want to convert 4 GB
Apply the conversion formula
Use the formula: GiB = GB × 10⁹ ÷ 1024³
Calculate the result
4 GB = 3.7253 GiB
Verify your answer
Use our calculator above to double-check your manual calculation.
Quick Mental Math Tip
A gigabyte is 1,000,000,000 bytes (SI decimal prefix). A gibibyte is 1024³ = 1,073,741,824 bytes (IEC 80000-13 binary prefix). Convert by taking the decimal byte count and dividing by 1024³, which gives 1 GB = 0.931322575 GiB. This single factor explains every "missing" gigabyte on a new drive: the capacity is decimal, the operating system's display is binary.
Common Conversions
| Gigabytes (GB) | Gibibytes (GiB) | Gibibytes → Gigabytes |
|---|---|---|
| 1 GB | 0.931323 | 1 GiB = 1.07374 GB |
| 2 GB | 1.86265 | 2 GiB = 2.14748 GB |
| 4 GB | 3.72529 | 4 GiB = 4.29497 GB |
| 8 GB | 7.45058 | 8 GiB = 8.58993 GB |
| 16 GB | 14.9012 | 16 GiB = 17.1799 GB |
| 32 GB | 29.8023 | 32 GiB = 34.3597 GB |
| 64 GB | 59.6046 | 64 GiB = 68.7195 GB |
| 120 GB | 111.759 | 120 GiB = 128.849 GB |
| 128 GB | 119.209 | 128 GiB = 137.439 GB |
| 240 GB | 223.517 | 240 GiB = 257.698 GB |
| 256 GB | 238.419 | 256 GiB = 274.878 GB |
| 500 GB | 465.661 | 500 GiB = 536.871 GB |
| 512 GB | 476.837 | 512 GiB = 549.756 GB |
| 1000 GB | 931.323 | 1000 GiB = 1,073.74 GB |
| 1024 GB | 953.674 | 1024 GiB = 1,099.51 GB |
| 2000 GB | 1,862.65 | 2000 GiB = 2,147.48 GB |
Did You Know?
Data storage units follow a binary system (1024) in computing but a decimal system (1000) in marketing — this is why your "500 GB" drive shows less space.
This converter is used by thousands of people daily for storage planning. Bookmark it for instant access.
When You'll Need This Conversion
Explaining advertised vs reported capacity
Convert a decimal capacity into gibibytes to reproduce the figure an operating system displays, and show the byte count is identical.
Sizing virtual machines and volumes
Hypervisors and cloud block storage mix GB and GiB in the same console. Converting once avoids provisioning a volume that is 7% smaller than intended.
Teaching SI vs IEC prefixes
The 0.9313 factor makes the 1000-vs-1024 distinction concrete instead of abstract.
Capacity reporting and audits
Normalise mixed vendor and OS figures to one convention before reporting utilisation.
Pro Tips for Accurate Conversions
The factor is 1.073741824
GiB → GB multiplies by 1.073741824; GB → GiB divides by it. The gap compounds: it is 2.4% at kilo, 4.9% at mega, 7.4% at giga and 10.0% at tera.
Read the label, not the number
If a tool reports "GB" but the arithmetic used 1024, the number is really GiB. Checking which divisor produced it resolves nearly every capacity dispute.
Provision in bytes where you can
Cloud APIs usually accept a byte count. Supplying bytes removes the prefix ambiguity entirely.
Common Mistakes to Avoid
Using 1024 with a decimal prefix
"1 MB = 1024 kB" mixes the SI prefix M with the binary factor 1024. Under SI and IEC 80000-13 the decimal prefixes are strictly powers of 1000, and 1024-based steps have their own prefixes (Ki, Mi, Gi, Ti).
1 MB = 1000 kB. 1 MiB = 1024 KiB. Pick the convention that matches your context and label it.
Comparing a manufacturer capacity to an OS capacity
Storage vendors report decimal bytes; Windows reports binary values under decimal labels. The two figures describe an identical number of bytes.
Convert both to raw bytes before comparing, then choose one convention for the final answer.
Assuming megabits and megabytes are interchangeable
Network speeds are quoted in megabits per second (Mbit/s), storage in megabytes (MB). There are 8 bits in a byte, so a 100 Mbit/s link moves at most 12.5 MB/s.
Divide bits by 8 to get bytes before comparing a link speed with a file size.
History & Background
When memory was addressed in powers of two, 2¹⁰ = 1024 was close enough to 1000 that engineers borrowed the SI prefix "kilo" for it. The approximation broke down as capacities grew: by the terabyte the two conventions differ by about 10%. In 1998 the IEC published the binary prefixes kibi, mebi, gibi and tebi (now IEC 80000-13) so that each convention has its own unambiguous name.
Key Milestones
Early computing informally uses "kilobyte" for 1024 bytes, a 2.4% deviation from the SI prefix.
IEC 60027-2 introduces the binary prefixes kibi (Ki), mebi (Mi), gibi (Gi) and tebi (Ti).
IEC 80000-13 supersedes it and remains the current international standard for information units.
Storage manufacturers, network equipment, macOS, iOS, Android and Linux report decimal; Windows still labels binary values with decimal prefixes.
Global Usage Today
SI decimal prefixes are the standard for storage capacity and data transfer worldwide. Binary prefixes dominate in memory, filesystem internals and low-level programming. The only real error is using one convention under the other's name.
Frequently Asked Questions
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Conversion factors on this page are either exact by definition, derived from exact definitions, or conventional values in documented use. Each is listed with its source in our conversion methodology and sources, which cites the BIPM SI Brochure, NIST Special Publication 811 and the relevant IEC or national standards. Results are rounded for display only; calculations use full precision.