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GB to TB Converter

Convert gigabytes to terabytes — 1,000 GB to the terabyte in the decimal units storage is sold in. Results update as you type; exact factors shown.

One gigabyte (10⁹) is 0.001 terabyte (10¹²) — see the exact factor, not a rounded rule of thumb.

Direction
Results update as you type
Results
1 GB in terabyte (10¹²)
0.001 TB
Conversion factor
Reverse conversion
In byte (base unit)
Reviewed September 2026. Exact conversion factors from the BIPM SI Brochure and NIST SP 811; The UK is metric for most trade and science but keeps miles, pints, stone and mpg (with the imperial gallon) in daily life.
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About data conversion

How the gb to tb converter works

Storage converts through the byte (8 bits). Drive makers and network speeds use decimal prefixes (1 GB = 10⁹ bytes); operating systems often report binary units (1 GiB = 2³⁰ = 1,073,741,824 bytes) — sometimes labelled "GB". The gap is 7.4% at the gigabyte and 10% at the terabyte.

The UK is metric for most trade and science but keeps miles, pints, stone and mpg (with the imperial gallon) in daily life.

Common data conversions

FromToUnits
100 GB0.1 TBgigabyte (10⁹) to terabyte (10¹²)
250 GB0.25 TBgigabyte (10⁹) to terabyte (10¹²)
500 GB0.5 TBgigabyte (10⁹) to terabyte (10¹²)
1,000 GB1 TBgigabyte (10⁹) to terabyte (10¹²)
2,000 GB2 TBgigabyte (10⁹) to terabyte (10¹²)
4,000 GB4 TBgigabyte (10⁹) to terabyte (10¹²)
8,000 GB8 TBgigabyte (10⁹) to terabyte (10¹²)
10,000 GB10 TBgigabyte (10⁹) to terabyte (10¹²)
12,000 GB12 TBgigabyte (10⁹) to terabyte (10¹²)
16,000 GB16 TBgigabyte (10⁹) to terabyte (10¹²)
20,000 GB20 TBgigabyte (10⁹) to terabyte (10¹²)
100,000 GB100 TBgigabyte (10⁹) to terabyte (10¹²)

Units in this converter and their exact factors

UnitSymbolOne unit in bytes
bitbit0.125 byte
byteB1 byte
kilobyte (10³)kB1,000 byte
megabyte (10⁶)MB1,000,000 byte
gigabyte (10⁹)GB1,000,000,000 byte
terabyte (10¹²)TB1,000,000,000,000 byte
kibibyte (2¹⁰)KiB1,024 byte
mebibyte (2²⁰)MiB1,048,576 byte
gibibyte (2³⁰)GiB1,073,741,824 byte
tebibyte (2⁴⁰)TiB1,099,511,627,776 byte

Frequently asked questions about data conversion

How many GB in a TB?

1,000 GB decimal, or 1,024 GiB binary.

How much is a terabyte in practice?

Roughly 250,000 photos, or about 40 hours of 4K video at 60 Mbps.

Why is my 4 TB drive smaller than 4 TB?

The operating system reports binary units — 4 TB decimal is 3.64 TiB.

How long to transfer a terabyte?

About two and a half hours on a saturated gigabit link; see the data transfer time calculator.

Should I plan storage in decimal or binary?

Buy in decimal, since that is what is sold, but size filesystems in binary, since that is what they report.

Where these figures come from

Last checked: September 2026. Conversion factors are fixed by definition and do not change with tax years or regulations.