Petabits

A petabit is a unit of information equal to 10^15 bits. It derives from the SI prefix peta for 10^15. In bytes, a petabit is 1.25 × 10^14 bytes, or about 125 terabytes. The term is used primarily to describe very large data transfer rates and storage capacities.

In common usage, data rates are expressed as petabits per second (Pb/s or Pbps). While individual networks are typically described in terabits per second, petabits per second are used for representing aggregated capacity in large-scale backbones or future megascale systems.

A related binary unit is the pebibit, equal to 2^50 bits (about 1.125 × 10^15 bits). The pebibit is roughly 1.125 petabits and, in bytes, about 1.407 × 10^14 bytes (roughly 140.7 terabytes). The binary and decimal prefixes can cause confusion, so it is important to specify whether decimal (petabit) or binary (pebibit) values are intended.

Petabits are rarely encountered in everyday consumer contexts but are used in discussions of global-scale networks, data-center interconnects, and theoretical capacities for future infrastructure. See also bits and bytes, and the related prefixes for data storage and transmission.