EIRP, or effective isotropically radiated power, or equivalent isotropically radiated power, is a measurement of output power in one direction from an ideal, one dimensional source. The ideal point-source radiates electromagnetic energy in a spherical pattern, so the "maximum" radiated power should be the same in all directions.
**Note: Like our EIRP calculator, all of our RF calculators allow SI prefix input. For example, if you wish to input "25000000", just type "25M" instead. See the quick-reference table below for all compatible SI prefixes.