Information units

Information units

Information units are used in the fields of information technology, telecommunications, and digital media and imaging. They include units for data storage, data flow rates and image resolution.

The SI does not include units of information, although some information units are derived from a combination of SI units and information units.

Examples of information units
Name Symbol Quantity Expressed in terms of SI base units
bit bit data
byte B data
pixel px picture element
pixel per metre px/m pixel resolution m-1
per square centimetre
Mpx/cm2 pixel density m-2
bit per second bit/s data rate s-1
byte per second B/s data rate s-1
bit per pixel bit/px colour depth


Multiples of information units can be formed using either SI prefixes, or IEC binary prefixes.

When SI prefixes are used with information units, they should be used only when referring strictly to multiples of powers of 10.