RMS Voltage Calculator

Standard RMS Voltage Calculator

RMS Voltage Equations:

V_RMS = V_peak / √2 (Sine wave) V_RMS = V_p-p / (2√2) (Peak-to-peak) V_RMS = V_avg × π / (2√2) (From average)

325V Peak

170V Peak

340V P-P

207V Avg

Peak Voltage (V_peak):

Peak-to-Peak (V_p-p):

Average Voltage (V_avg):

Enter any voltage value to calculate RMS voltage

Auto-calculate as you type

0 V_RMS

0 V 120 V 240 V 480 V

Note: The RMS meter shows the effective (heating) value of AC voltage.

Waveform-Specific RMS Calculator

Waveform RMS Factors:

Sine Wave: V_RMS = V_peak / √2 (0.707) Square Wave: V_RMS = V_peak (1.0) Triangle Wave: V_RMS = V_peak / √3 (0.577) Sawtooth Wave: V_RMS = V_peak / √3 (0.577)

Peak Voltage (V_peak):

Frequency (Hz) - Optional:

Select waveform type and enter peak voltage

Waveform Visualization: Real-time display of selected waveform with RMS indication.

AC/DC Conversion Calculator

AC to DC Conversion:

Half-wave rectifier: V_DC = V_RMS × 0.45 Full-wave rectifier: V_DC = V_RMS × 0.637 Bridge rectifier: V_DC = V_RMS × 0.9 (with filter)

AC RMS Voltage Input:

Rectifier Type:

Load Current (A) - Optional:

Enter AC RMS voltage to calculate DC output

Parameter	Value	Unit
AC RMS Input	-	V
DC Output	-	V
Peak Voltage	-	V
Ripple Factor	-	%
Power (if current given)	-	W

Note: Values assume ideal components. Real circuits may have additional losses.

Advanced RMS Calculator

Advanced RMS Calculations:

Multi-harmonic RMS: V_RMS = √(V₁² + V₂² + V₃² + ...) THD calculation: THD = √(V₂² + V₃² + ...) / V₁ Crest Factor: CF = V_peak / V_RMS

Harmonic Analysis

Fundamental (V₁):

2nd Harmonic (V₂):

3rd Harmonic (V₃):

5th Harmonic (V₅):

Custom Measurement Points (comma-separated):

Enter harmonic components or measurement points

Parameter	Value
Total RMS	-
THD (%)	-
Crest Factor	-
Form Factor	-

Understanding RMS Voltage

Root Mean Square (RMS) voltage is the effective value of an AC voltage that produces the same heating effect as an equivalent DC voltage. It's calculated as the square root of the mean of the squares of instantaneous values.

V_RMS = V_peak / √2 - For sine waves (most common)
V_RMS = V_peak - For square waves
V_RMS = V_peak / √3 - For triangle and sawtooth waves

Example 1: Household AC Voltage

Standard US household voltage has a peak of 170V. What is the RMS voltage?

Solution: V_RMS = 170 / √2 = 170 / 1.414 = 120.2 V

Example 2: Square Wave RMS

A square wave oscillates between +15V and -15V. What is the RMS voltage?

Solution: For square waves, V_RMS = V_peak = 15 V

Example 3: Triangle Wave

A triangle wave has a peak voltage of 24V. Calculate the RMS voltage.

Solution: V_RMS = 24 / √3 = 24 / 1.732 = 13.86 V

Example 4: Harmonic Analysis

A distorted sine wave has: Fundamental = 100V, 3rd harmonic = 20V, 5th harmonic = 10V. Find total RMS.

Solution: V_RMS = √(100² + 20² + 10²) = √(10000 + 400 + 100) = 102.47 V