Conversion formula (Decimal vs. Binary)
Data storage measurement utilizes two main standard conventions: the International System of Units (SI decimal) and the International Electrotechnical Commission (IEC binary) standard.
GB to TB Formulas
Decimal Standard (SI): $\text{Terabytes (TB)} = \frac{\text{Gigabytes (GB)}}{1,000}$
Binary Standard (IEC): $\text{Tebibytes (TiB)} = \frac{\text{Gibibytes (GiB)}}{1,024}$
Example Calculation (5,000 GB):
• Decimal: $5,000 \div 1,000 = \mathbf{5.00\text{ TB}}$
• Binary: $5,000 \div 1,024 = \mathbf{4.8828\text{ TiB}}$
GB to TB conversion reference table
Quick lookup guide for common storage capacities comparing decimal Terabytes against Windows binary system values:
| Gigabytes (GB) | Decimal Terabytes (TB) | Binary Tebibytes (TiB / OS Display) | Typical Data Scale |
|---|---|---|---|
| 250 GB | 0.25 TB | 0.2328 TiB | Base laptop SSD drive capacity |
| 500 GB | 0.50 TB | 0.4656 TiB | Gaming console internal storage |
| 1,000 GB | 1.00 TB | 0.9313 TiB | Standard external hard drive unit |
| 2,000 GB | 2.00 TB | 1.8626 TiB | High-capacity cloud backup tier |
| 5,000 GB | 5.00 TB | 4.6566 TiB | 4K video archive workstation storage |
Why does your 1 TB drive show as 931 GB?
This discrepancy stems from how hardware manufacturers and operating systems define digital units:
- Hardware Manufacturers (Decimal): Standardize on powers of 10. $1\text{ TB} = 1,000,000,000,000\text{ bytes}$ ($10^{12}$).
- Operating Systems like Windows (Binary): Process storage using base-2 powers ($2^{10} = 1,024$). Windows divides bytes by $1,024^3$ to compute gigabytes, rendering $1,000,000,000,000 \div 1,073,741,824 \approx \mathbf{931.32\text{ GB}}$.
- macOS & Linux: Modern Apple macOS systems align with SI decimal standards, displaying 1 TB as 1,000 GB.
How to use this calculator
- Type the value in Gigabytes into the input field.
- View instant outputs for both standard decimal Terabytes (TB) and binary Tebibytes (TiB).
Frequently asked questions
How many GB are in a TB?
1,000 GB under the decimal standard used here, or 1,024 GB under the binary standard.
Why is my '1 TB' hard drive shown as about 931 GB?
The drive manufacturer uses decimal TB (1,000 GB), while your operating system typically reports capacity in binary GB (1,024-based), producing a smaller displayed number for the same physical drive.
How do I convert TB back to GB?
Multiply the number of terabytes by 1,000.
Is this conversion relevant beyond storage drives?
Yes, it applies anywhere data volumes are measured at this scale, including cloud storage plans and large data transfers.