Bytes to GB Converter
Enter a number of bytes to see both answers.
What Google, macOS, drive makers and internet providers use.
The unit Windows Explorer labels “GB”, and how RAM is sized.
Other conversions: Bytes to KB · Bytes to MB
How to Convert Bytes to GB
A gigabyte comes in two sizes, and both are in everyday use. A decimal gigabyte (GB) is 1,000,000,000 bytes (109). Drive and phone makers print it on the box, and macOS and Google’s calculator count in it. A binary gigabyte, correctly called a gibibyte (GiB), is 1,073,741,824 bytes (230). Windows counts in gibibytes but labels them “GB”, and RAM is always sold in them.
- GB (decimal) = bytes ÷ 1,000,000,000
- GiB (binary) = bytes ÷ 1,073,741,824
For the decimal answer you don’t need a calculator: move the decimal point nine places to the left. 4,294,967,296 bytes are 4.294967296 GB. The binary answer needs a real division, and it always comes out about 6.9 percent smaller: the same 4,294,967,296 bytes are exactly 4 GiB.
Why Does a 1 TB Drive Show Only 931 GB?
The maker sells you 1,000,000,000,000 bytes and calls it 1 TB, in decimal units. Windows divides the same number by 1,073,741,824 and shows 931 GB. No space is missing: 931.32 GiB and 1 TB are the same number of bytes. The gap grows with every prefix. A binary unit is 2.4 percent larger than its decimal twin at kilo, 4.9 percent at mega, 7.4 percent at giga and 10 percent at tera. That is why the difference hardly shows for small files but becomes very visible on a new drive.
A new phone or drive also shows less free space than this. The file system, a recovery partition and the operating system take their share, and that space really is used. The step from 1,000 to 931 is only a change of units.
Which Number Does My Computer Show?
- Windows (File Explorer, This PC, Disk Management): binary. A “1 TB” drive appears as 931 GB, a file of 4,294,967,296 bytes as 4.00 GB. Use the binary answer above.
- macOS (Finder, Disk Utility) and iPhone/iPad storage settings: decimal. The same drive appears as 1 TB. Use the decimal answer.
- Linux:
df -h,du -handls -lhcount in 1,024s and print “G”;df -Hor--siswitches to decimal. - RAM: binary. “16 GB” of memory is 16 GiB, or 17,179,869,184 bytes.
- Google’s calculator and drive packaging: decimal.
Bytes to GB Conversion Table
Typical sizes from memory, files and storage, with both answers. The decimal values are exact, the binary ones rounded to six decimal places.
| Bytes | GB (decimal) | GiB (binary, Windows “GB”) |
|---|---|---|
| 1,000,000 (1 MB) | 0.001 | 0.000931323 |
| 1,048,576 (1 MiB) | 0.001048576 | 0.0009765625 |
| 100,000,000 | 0.1 | 0.093132 |
| 134,217,728 (128 MiB) | 0.134217728 | 0.125 |
| 500,000,000 | 0.5 | 0.465661 |
| 536,870,912 (512 MiB) | 0.536870912 | 0.5 |
| 1,000,000,000 (1 GB) | 1 | 0.931323 |
| 1,073,741,824 (1 GiB) | 1.073741824 | 1 |
| 2,147,483,648 (2 GiB) | 2.147483648 | 2 |
| 4,294,967,296 (4 GiB, the FAT32 file limit is 1 byte less) | 4.294967296 | 4 |
| 8,589,934,592 (8 GiB) | 8.589934592 | 8 |
| 10,000,000,000 | 10 | 9.313226 |
| 17,179,869,184 (16 GiB) | 17.179869184 | 16 |
| 34,359,738,368 (32 GiB) | 34.359738368 | 32 |
| 64,000,000,000 (“64 GB” memory card) | 64 | 59.604645 |
| 128,000,000,000 (“128 GB” phone) | 128 | 119.20929 |
| 256,000,000,000 (“256 GB” SSD) | 256 | 238.418579 |
| 512,000,000,000 (“512 GB” SSD) | 512 | 476.837158 |
| 1,000,000,000,000 (“1 TB” drive) | 1,000 | 931.322575 |
| 2,000,000,000,000 (“2 TB” drive) | 2,000 | 1,862.645149 |
Smaller numbers read better in another unit: see bytes to MB and bytes to KB. The Byte / Data Size Converter shows any value in all 18 units at once, terabytes and bits included.
Frequently Asked Questions
How many bytes are in 1 GB?
1 GB is 1,000,000,000 bytes in the decimal (SI) system. The “GB” that Windows shows is a gibibyte (GiB): 1,073,741,824 bytes, or 1,024 × 1,024 × 1,024.
How many GB is 1,073,741,824 bytes?
1,073,741,824 bytes are 1.073741824 GB in decimal and exactly 1 GiB in binary. Windows shows such a file as 1.00 GB, Google’s calculator as about 1.07 GB.
How many GB is 1,048,576 bytes?
0.001048576 GB in decimal and 0.0009765625 GiB in binary. 1,048,576 bytes are exactly 1 MiB, so for a number this small megabytes are easier to read: 1.05 MB in decimal, or 1 MB as Windows shows it.
How do I convert GB back to bytes?
Multiply instead of divide: decimal GB × 1,000,000,000, or binary GiB × 1,073,741,824. 8 GB are 8,000,000,000 bytes; 8 GiB are 8,589,934,592 bytes. To start from gigabytes, open the Byte Converter with GB selected.