OctaCalc / Peak-to-Peak Voltage Calculator

Peak-to-Peak Voltage Calculator

Convert between RMS voltage, peak voltage, and peak-to-peak voltage (Vpp) for sine, square, and triangle waveforms. Enter either an RMS or peak value and get all three representations instantly.

Formula: Vpp = 2 × √2 × Vrms

How to Use This Calculator

Select whether you're starting from an RMS voltage or a Peak voltage using the toggle at the top. Then choose your waveform type and enter the voltage value. The calculator instantly outputs peak-to-peak voltage (Vpp), peak voltage (Vpeak), and RMS voltage (Vrms).

Use the unit selector to enter values in volts (V), millivolts (mV), or kilovolts (kV) — all results are displayed in appropriately scaled units. Hit Reset to clear the inputs and start fresh.

Formula

Sine Wave

Vpp = 2 × Vpeak
Vpp = 2 × √2 × Vrms ≈ 2.828 × Vrms
Vpeak = √2 × Vrms ≈ 1.414 × Vrms

Square Wave

Vpp = 2 × Vpeak
Vpp = 2 × Vrms
Vpeak = Vrms

Triangle Wave

Vpp = 2 × Vpeak
Vpp = 2 × √3 × Vrms ≈ 3.464 × Vrms
Vpeak = √3 × Vrms ≈ 1.732 × Vrms

Where: Vpp = peak-to-peak voltage, Vpeak = peak voltage, Vrms = RMS (root mean square) voltage.

Example

Given: Sine wave, Vrms = 12 V

Vpp = 2 × √2 × Vrms

Vpp = 2 × 1.414 × 12

Vpp = 33.94 V

Vpeak = √2 × 12 = 16.97 V

Frequently Asked Questions

What is peak-to-peak voltage?
Peak-to-peak voltage (Vpp) is the total voltage swing from the most negative point to the most positive point of an AC waveform. It equals twice the peak voltage for symmetrical waveforms.

Why does the formula differ between waveform types?
RMS voltage represents the effective DC-equivalent heating value of an AC signal. The relationship between RMS and peak depends on the waveform shape — a sine wave's crest factor (Vpeak / Vrms) is √2, a square wave's is 1, and a triangle wave's is √3.

What is crest factor?
Crest factor is the ratio of peak voltage to RMS voltage. Sine wave: √2 ≈ 1.414. Square wave: 1.0. Triangle wave: √3 ≈ 1.732. A higher crest factor means the waveform has sharper peaks relative to its average power.

When would I use peak voltage instead of RMS?
Peak voltage is used to assess insulation ratings, component voltage ratings, and oscilloscope readings. RMS is used for power calculations and when comparing to DC voltages.

Does this calculator work for non-symmetrical waveforms?
This calculator assumes symmetrical waveforms (equal positive and negative peaks). For asymmetric or complex waveforms, a proper waveform analyser or oscilloscope is needed.