RF Exposure Calculator

Calculate power density at distance for FCC RF exposure compliance. Checks controlled and uncontrolled environment MPE limits.

Transmitter Power

Antenna Gain

dBi

Distance to Person

Frequency

MHz

Duty Cycle

Tab to move between fields

Power Density

0.07057 mW/cm²

% of Uncontrolled Limit

35.28 %

Uncontrolled compliant

Yes

Min Safe Distance (Uncontrolled)

1.78 m

MPE Limit (Controlled)1 mW/cm²

MPE Limit (Uncontrolled)0.2 mW/cm²

% of Controlled Limit7.06 %

Controlled compliantYes

Average ERP79.81 W

How to Use This Calculator

Enter transmitter output power (W) and antenna gain (dBd or dBi).
Set the distance from the antenna to the nearest person (meters) and operating frequency (MHz).
Enter your duty cycle (%) — the fraction of time actually transmitting.
Review power density (mW/cm²) and compare to FCC MPE limits for controlled and uncontrolled environments.
Ensure you are below 100% of the uncontrolled MPE limit for general public areas.

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Formula

S = (P × G × D%) / (4πd²); FCC OET Bulletin 65

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