How to Convert Terabytes to Gigabytes (TB to GB)

Updated 5 Oct 2026 in Unit Converters

Data conversions explain why a 1 TB drive shows less space on your computer and help compare mobile plans sold in gigabytes. This guide shows how to convert terabytes into gigabytes by hand, with examples and a quick-reference table.

The conversion

To convert terabytes to gigabytes, multiply the value by 1,000. To go the other way, divide by the same number (or multiply by 0.001). For a quick estimate, multiply by about 1,000.

Gigabytes = terabytes × 1,000

Worked examples

Terabytes to Gigabytes table

TerabytesGigabytes
1 TB1,000 GB
2 TB2,000 GB
5 TB5,000 GB
10 TB10,000 GB
20 TB20,000 GB
25 TB25,000 GB
50 TB50,000 GB
100 TB100,000 GB
250 TB250,000 GB
500 TB500,000 GB
1,000 TB1,000,000 GB

Common questions

Is TB to GB exact?

The factors used here are the internationally defined values where they exist; results are rounded for display only.

How do I convert back?

Use the Gigabytes to Terabytes converter.

Mistakes to avoid

Rounding the factor too early

Using 3 instead of 3.28 for feet per metre introduces an error of almost 9% before you have started.

Mixing similar-sounding units

US and imperial gallons, pints and tons are different sizes, and decimal kilobytes differ from binary kibibytes.

Multiplying when you should divide

Converting to a smaller unit gives a bigger number, and converting to a larger unit gives a smaller one. If your answer moves the wrong way, you have inverted the factor.

Background

Many conversion factors are exact by definition. The inch has been defined as exactly 2.54 centimetres since 1959, and the pound as exactly 0.45359237 kilograms, so conversions involving them can be as precise as you need.

For everyday use, three or four significant figures are usually enough. Engineering, science and trade documents may need more, and rounding should happen only at the end of a calculation.

Unit conversion is simply multiplication by a fixed ratio. The ratio between two units of the same quantity never changes, so once you know it you can convert any value in either direction.

For any value, use the Terabytes to Gigabytes Converter or browse all data storage converters.

Run your own numbers: Terabytes to Gigabytes Converter

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