1 terabit = 10¹² bits = 1,000,000,000,000 bits (one trillion, or, using the long scale, one billion). 1 terabit is equal to 125 (decimal) gigabytes or 122 (binay) gibibytes.

The terabit is closely related to the tebibit, which is equal to 2⁴⁰ or 1,099,511,627,776 bits. Note that the difference between a trillion bits and a tebibit is about 10%.