Peak-to-Peak Voltage Calculator

How it is calculated

You enter the amplitude, meaning the peak voltage measured from the zero line to the top of the wave, in volts. The tool applies Vpp = 2 × Vpeak and Vrms = Vpeak ÷ √2, where √2 ≈ 1.4142. Both results are shown in volts with two decimals. The RMS formula is valid for a pure sine wave only; a square, triangle or distorted wave has a different ratio between peak and RMS. The doubling for Vpp assumes the wave swings equally above and below zero, so a signal with a DC offset needs separate treatment. A negative amplitude returns no result because amplitude is a magnitude; zero returns 0.00 V for both outputs.

Common mistakes

• Typing the peak-to-peak reading from a scope into the amplitude field. The field wants the half-swing (zero to peak), so enter half of what you measured.
• Assuming RMS equals peak ÷ √2 for any waveform. That ratio holds for sine waves; for a square wave RMS equals the peak, so the RMS result here would be wrong.
• Ignoring DC offset: if the wave is centred at 2 V rather than 0 V, the swing is still 2 × the amplitude about its own centre, not 2 × the highest voltage on the screen.
• Comparing a Vpp figure to an RMS rating (such as a mains or speaker spec) without converting, which is off by a factor of about 2.83.
• Entering a negative amplitude to represent the bottom of the wave; the tool rejects negatives, so enter the positive magnitude.