RMS Voltage Calculator
Enter the known values and run the calculation.
Enter the known voltage, choose whether it is peak or peak-to-peak, and run the calculation.
The result reports the corresponding RMS voltage in volts.
Overview
Convert waveform values into RMS voltage for power-equivalent measurements in AC circuits.
Use this tool to convert peak or peak-to-peak voltage into RMS voltage for the sine-wave case.
It is useful when a waveform is described one way on the scope but power or heating needs to be discussed in RMS terms.
The math and how it's used
These relationships assume a sinusoidal waveform.
If the source waveform is not sinusoidal, use the waveform-specific RMS relationship instead.
RMS voltage is the practical quantity for power, heating, and many instrument specs, so this is useful when scope-style amplitude numbers have to be translated into that form.
The conversion factors here are for sine waves. Once the waveform stops looking sinusoidal, the RMS relationship needs to come from the actual shape instead.
What to watch
The conversion constants here are for sinusoidal waveforms. They do not hold for square, pulsed, clipped, or arbitrary waveforms.
If the waveform is not close to a sine wave, measure RMS directly or use the correct waveform-specific expression.