TB to GB Converter Form
Decimal mode uses standard storage marketing units. Binary reference mode helps compare operating-system style capacity reporting.
Example Data Table
| Capacity per Drive | Drive Count | Standard | Reserve % | Filesystem % | Usable Output |
|---|---|---|---|---|---|
| 2.00 TB | 1 | Decimal | 5 | 0 | 1,900.00 GB |
| 4.00 TB | 2 | Decimal | 10 | 2 | 7,056.00 GB |
| 1.50 TB | 3 | Binary reference | 2 | 1 | 4,470.68 GiB |
These examples show how reserve space, overhead, and conversion standard can change final available capacity.
Formula Used
Gross TB = Capacity per Drive × Drive Count
Usable TB = Gross TB × (1 − Reserve % ÷ 100) × (1 − Filesystem Overhead % ÷ 100)
Converted Gross Capacity = Gross TB × Conversion Factor
Converted Usable Capacity = Usable TB × Conversion Factor
Converted Capacity Loss = Converted Gross Capacity − Converted Usable Capacity
Decimal mode: 1 TB = 1000 GB.
Binary reference mode: 1 TiB = 1024 GiB.
Custom mode: You choose any factor for specialized storage planning, internal standards, or vendor-specific sizing models.
How to Use This Calculator
- Enter the terabyte value for one drive or storage unit.
- Add the number of drives you want to total.
- Choose decimal, binary reference, or a custom conversion factor.
- Enter reserved space and filesystem overhead percentages if needed.
- Select the number of decimal places for the output.
- Press Convert Now to view the result above the form.
- Review the chart and summary table for gross, usable, and lost capacity.
- Use the CSV or PDF buttons to save the result for documentation.
Frequently Asked Questions
1) What is the standard TB to GB conversion?
The decimal storage standard uses 1 TB = 1000 GB. This is the value most drive makers use on labels, packaging, and product specification sheets.
2) Why does binary mode use 1024?
Binary capacity reporting follows powers of two. In strict IEC notation, 1 TiB equals 1024 GiB. This mode helps compare displayed storage against operating-system style references.
3) Why is usable capacity lower than gross capacity?
Reserved space and filesystem overhead reduce the amount you can actually use. Formatting, metadata, recovery partitions, and spare capacity planning all lower visible storage.
4) Can I calculate multiple drives at once?
Yes. Enter the capacity for one drive, then add the drive count. The calculator totals raw capacity first and then applies your selected deductions.
5) When should I use a custom factor?
Use a custom factor when your team follows a special planning rule, vendor-specific estimate, or internal conversion model for forecasting storage requirements.
6) Does this tool support storage planning?
Yes. It is useful for capacity forecasts, SAN sizing, backup projections, workstation storage estimates, and comparing raw device totals with usable space.
7) What do the CSV and PDF exports include?
The exports include the standard used, factor, raw capacity, usable capacity, loss values, per-drive output, and decimal plus binary reference figures.
8) Is this calculator only for hard drives?
No. You can use it for SSDs, arrays, virtual storage pools, cloud storage planning, backup targets, and any capacity model measured from terabytes.