Calculate rms voltage

For a zero-offset sine wave, RMS voltage = peak voltage ÷ √2.

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Sine-wave peak voltage (V)

Answer

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For a zero-offset sine wave, RMS voltage = peak voltage ÷ √2.

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Formula and assumptions

This relationship is specific to sinusoidal voltage. Square waves, pulse trains, DC offsets, and distorted waveforms need a different calculation.

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Updated 2026-09-26

Using Calculate rms voltage

For a zero-offset sine wave, RMS voltage = peak voltage ÷ √2.

This relationship is specific to sinusoidal voltage. Square waves, pulse trains, DC offsets, and distorted waveforms need a different calculation.

Next: Basic calculator

A worked example

With sine-wave peak voltage (v) = 100, the rms voltage (v) is 70.71067811865476.

Before you use the result

This relationship is specific to sinusoidal voltage. Square waves, pulse trains, DC offsets, and distorted waveforms need a different calculation.

Example results for sine-wave peak voltage (v)

These examples use the formula above. They are reference calculations, not recommended settings.

Sine-wave peak voltage (V)	RMS voltage (V)
50	35.3553390593
100	70.7106781187
200	141.421356237

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