EIRP Calculator

Calculate Effective Isotropic Radiated Power (EIRP), ERP, and power density for RF transmitters.

EIRP Parameters

EIRP = Pt - Lc + Ga
ERP = EIRP - 2.15 dB

EIRP Result

38.00 dBm
6.31 W
35.85
ERP (dBm)
8.00
EIRP (dBW)

Calculation Breakdown

TX Power+30.00 dBm
Cable Loss-2.00 dB
Antenna Gain+10.00 dBi
EIRP38.00 dBm

Power Density

@ 1 m502.10 mW/m^2
@ 10 m5.02 mW/m^2
@ 100 m50.21 mW/m^2
@ 1000 m502.10 uW/m^2

Common EIRP Limits

ApplicationEIRP Limit
WiFi 2.4GHz (US)36 dBm (4W)
WiFi 5GHz (US)30 dBm (1W)
WiFi 2.4GHz (EU)20 dBm (100mW)
ISM 900MHz36 dBm (4W)
LoRa 868MHz (EU)14 dBm (25mW)
LoRa 915MHz (US)30 dBm (1W)