GB to TB Converter
Enter a size in gigabytes and see it in terabytes. The converter divides by 1,024 unless you tick the SI box, which divides by 1,000.
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Created by the Reeliy Editorial Team. Last updated: Oct 19, 2026
How many gigabytes are in a terabyte?
A terabyte holds 1,024 gigabytes in the binary convention and 1,000 gigabytes in the SI convention. Storage manufacturers and standards bodies use the second; many operating systems calculate with the first.
binary: TB = GB ÷ 1,024
SI: TB = GB ÷ 1,000
This converter divides by 1,024 by default. Ticking Use SI standard divides by 1,000, and the answer is refreshed from the number already entered.
Difference between GB and TB
Terabytes describe the capacity of whole drives, servers and backup libraries, while gigabytes describe what sits on them: a game install, a phone backup, a season of video. Moving up one prefix makes the number roughly a thousand times smaller.
The prefix mismatch explains a familiar puzzle. A drive sold as 1 TB stores 1,000,000,000,000 bytes. A system that counts in binary divides by 1,073,741,824 to get gigabytes and reports about 931.3 GB, even though nothing is missing. The binary unit is properly called a gibibyte (GiB), and 1 tebibyte (TiB) is 1,024 GiB.
How to convert GB to TB
- Enter the number of gigabytes.
- Pick binary or SI using the checkbox.
- The TeraBytes box shows the converted value straight away.
The result keeps up to four decimal places, so a value like 0.4883 TB can appear, and anything below 0.00005 TB shows as 0. An empty GB box leaves the last answer unchanged.
Example: a 500 GB drive
In binary terms 500 ÷ 1,024 = 0.4883 TB. In SI terms 500 ÷ 1,000 = 0.5 TB. A 2,000 GB archive works out to 1.9531 TB (binary) or exactly 2 TB (SI).
GB to TB conversion table
| Gigabytes (GB) | TB, binary (÷ 1,024) | TB, SI (÷ 1,000) |
|---|---|---|
| 100 | 0.0977 | 0.1 |
| 250 | 0.2441 | 0.25 |
| 256 | 0.25 | 0.256 |
| 500 | 0.4883 | 0.5 |
| 512 | 0.5 | 0.512 |
| 1,000 | 0.9766 | 1 |
| 1,024 | 1 | 1.024 |
| 2,000 | 1.9531 | 2 |
| 2,048 | 2 | 2.048 |
| 4,000 | 3.9063 | 4 |
| 5,000 | 4.8828 | 5 |
| 10,000 | 9.7656 | 10 |
To work from terabytes instead, use the TB to GB converter. For a step down in size see GB to MB.
Common mistakes
- Expecting the full label capacity in the operating system. A 2 TB drive holds 2,000,000,000,000 bytes, which a binary-counting system shows as about 1,862.6 GB. Tick the SI box to see the manufacturer's number instead.
- Mixing GB with Gb. A capital B is bytes and a lowercase b is bits, so 1,000 Gb is only 125 GB.
- Rounding too early. Convert first and round at the end; 1,000 GB is 0.9766 TB in binary but a clean 1 TB in SI.
Frequently asked questions
How many GB are in 1 TB?
There are 1,024 GB in a binary terabyte and 1,000 GB in an SI terabyte.
How do I convert GB to TB?
Divide the gigabytes by 1,024 for binary or by 1,000 for SI. For example, 750 GB is 0.7324 TB in binary and 0.75 TB in SI.
Why does my 1 TB drive show about 931 GB?
The maker counts 1 TB as 1,000,000,000,000 bytes. Your system divides that by 1,073,741,824 bytes per gibibyte and labels the answer GB, giving about 931.3. No capacity is lost.
Is 1,000 GB the same as 1 TB?
Yes under SI. Under the binary convention 1,000 GB is only 0.9766 TB, because a binary terabyte needs 1,024 GB.
References
Cite this converter and page
If you use this page in your work, you can cite it as:
Reeliy Editorial Team. (2026). GB to TB Converter. Reeliy. https://reeliy.com/converters/convert-gb-to-tb“GB to TB Converter.” Reeliy, 2026, https://reeliy.com/converters/convert-gb-to-tb.