Gigabytes (GB) to Terabytes (TB) Converter

File sizes here use the decimal (SI) system, the same one drive makers and network providers use. In that system 1 Gigabyte is 10⁹ bytes and 1 Terabyte is 10¹² bytes. Divide one by the other and you get the ratio between the two units: 10⁹ ÷ 10¹² = 10⁻³.

Gigabyte is the smaller unit, so you divide. One GB is only 0.001 of a TB, which means the decimal point moves 3 places to the left.

These two sit side by side on the ladder (B → KB → MB → GB → TB → PB → EB → ZB → YB → RB → QB), so there is nothing to work out beyond remembering that every step is a factor of 1,000.

Need the other direction? Open the TB to GB converter.

A gigabyte is 1,000 megabytes, about 250 photos at 4 MB each. Gigabytes are the language of phone storage, RAM, mobile data plans, game installs and USB sticks.

A terabyte is 1,000 gigabytes, about 250,000 photos at 4 MB each. Terabytes are how consumer SSDs, external drives, home NAS boxes and cloud storage plans are sold.

Going from gigabytes up to terabytes always gives a smaller number, because you are counting in bigger chunks. People do it to make a long number readable, or to compare a file with the size of a drive or a plan.