# Terabytes to Gigabytes (TB to GB)

> Convert terabytes to gigabytes: 1 TB = 1000 GB. Exact conversion factor, formula, 18-row table and worked examples, with JSON API and MCP access.

- Page id: `tb-to-gb` · Quantity: Data storage (`data-storage`, base unit B) · Tool: `convert_units`
- Canonical page: https://tttkmbb.com/conversion/tb-to-gb · This document: https://tttkmbb.com/conversion/tb-to-gb.md · JSON: https://tttkmbb.com/conversion/tb-to-gb.json (add `?value=` for a result)

## Formula

- `1 TB = 1000 GB`
- `gigabytes = terabytes × 1000`
- Reverse: `terabytes = gigabytes × 0.001`

The factor follows from the SI definitions of both units (NIST SP 811); values below are rounded to 6 significant figures, the API returns up to 12.

## Worked examples

- 1.5 TB = 1500 GB
- 700 TB = 700000 GB
- 2048 TB = 2048000 GB

## Conversion table

| Terabytes (TB) | Gigabytes (GB) |
| --- | --- |
| 1 | 1000 |
| 2 | 2000 |
| 4 | 4000 |
| 8 | 8000 |
| 16 | 16000 |
| 32 | 32000 |
| 64 | 64000 |
| 100 | 100000 |
| 128 | 128000 |
| 256 | 256000 |
| 500 | 500000 |
| 512 | 512000 |
| 1000 | 1000000 |
| 1024 | 1024000 |
| 2048 | 2048000 |
| 4096 | 4096000 |
| 8192 | 8192000 |
| 10000 | 10000000 |

## API

- `GET https://tttkmbb.com/api/v1/convert?value=1.5&from_unit=TB&to_unit=GB` → unified JSON envelope with `result.values.result`, `formula`, `factor`, `sources`, `freshness`
- MCP: server `https://tttkmbb.com/mcp`, tool `convert_units` with `{"value":1.5,"from_unit":"TB","to_unit":"GB"}`
- All data storage units: https://tttkmbb.com/api/v1/units?quantity=data-storage · full converter: [Data Storage Converter](https://tttkmbb.com/conversion/data-storage.md)
- Authentication: none. Freshness: `static` (fixed conversion factors).

## FAQ

**How many gigabytes are in one terabyte?**

1 TB = 1000 GB. The factor comes from the SI definitions of both units (NIST SP 811 / BIPM), so it is exact or correct to at least 10 significant figures.

**What is the formula to convert terabytes to gigabytes?**

Multiply the value in terabytes by 1000: gigabytes = terabytes × 1000. For example, 1.5 TB = 1500 GB.

**How do I convert gigabytes back to terabytes?**

Multiply by the inverse factor 0.001 (terabytes = gigabytes × 0.001), or use the gigabytes-to-terabytes page.

## Related conversions

- [Gigabytes to terabytes](https://tttkmbb.com/conversion/gb-to-tb.md) (reverse)
- [Megabytes to Gigabytes](https://tttkmbb.com/conversion/mb-to-gb.md)
- [Gigabytes to Megabytes](https://tttkmbb.com/conversion/gb-to-mb.md)
- [Kilobytes to Megabytes](https://tttkmbb.com/conversion/kb-to-mb.md)
- [Megabytes to Kilobytes](https://tttkmbb.com/conversion/mb-to-kb.md)
- [Mebibytes to Megabytes](https://tttkmbb.com/conversion/mib-to-mb.md)
- [Megabytes to Mebibytes](https://tttkmbb.com/conversion/mb-to-mib.md)
- [Gibibytes to Gigabytes](https://tttkmbb.com/conversion/gib-to-gb.md)
- [Gigabytes to Gibibytes](https://tttkmbb.com/conversion/gb-to-gib.md)

## Data Sources

- NIST Special Publication 811 – Guide for the Use of the International System of Units (SI), Appendix B conversion factors — https://www.nist.gov/pml/special-publication-811 (standard, retrieved 2026-09-24)
- BIPM – The International System of Units (SI Brochure, 9th edition) — https://www.bipm.org/en/publications/si-brochure (standard, retrieved 2026-09-24)
- Wikipedia – Conversion of units — https://en.wikipedia.org/wiki/Conversion_of_units (reference, retrieved 2026-09-24)