# dBm-Voltage-Power Calculator

## About this calculator

This calculator converts between signal powers in dBm (decibel-milliwatts) or W and root mean square (RMS) and peak-to-peak voltages for a given impedance $Z$. Taking power in dBm $P_{\text{dBm}}$ as the starting point, power in linear scale (milliwatts) is

$P = 10^{\frac{P_{\text{dBm}}}{10}}$

This can be converted to watts and finally to RMS voltage using

$P = \dfrac{V_{\text{RMS}}^{2}}{Z}$

$V_{\text{RMS}} = \sqrt{PZ}$

Assuming sinusoidal signal, the peak-to-peak voltage is then

$V_{\text{pp}} = 2\sqrt{2}V_{\text{RMS}}$