Convert between RF power and voltage levels. Choose an impedance, then enter any one value; the remaining values update automatically in your browser.

mW
W
dBm
dBW
V
V
Vpp
dBmV

Conversion notes

The voltage conversions assume a sine wave across a purely resistive load. The calculator uses RMS voltage as the link between power and voltage:

P = Vrms² / R
Vpeak = Vrms × √2
Vpp = 2 × Vpeak
dBm = 10 × log₁₀(P / 1 mW)
dBmV = 20 × log₁₀(Vrms / 1 mV)

In RF systems, 50 Ω is the most common impedance. Cable television and video systems commonly use 75 Ω, while 600 Ω is historically associated with balanced audio and telecommunications circuits.

Useful reference points

dBmPower
-30 dBm1 µW
-20 dBm10 µW
-10 dBm100 µW
0 dBm1 mW
10 dBm10 mW
20 dBm100 mW
30 dBm1 W
40 dBm10 W

Adding 3 dB approximately doubles power; adding 10 dB multiplies power by ten.