Alternating Current
Total Harmonic Distortion Calculator
Total Harmonic Distortion converts the entered electrical measurements into total harmonic distortion. Use it to calculate THD from combined harmonic RMS.
Enter values for total harmonic distortion
Use one consistent electrical operating case for all fields.
How Total Harmonic Distortion works
For this case, apply THD = harmonic RMS ÷ fundamental RMS × 100. Total Harmonic Distortion uses RMS of harmonic components, Fundamental RMS value to report Total harmonic distortion.
With the loaded values, total harmonic distortion evaluates to 5.22%. Compare low and high values without overwriting the starting case. Use Peak-to-Peak Voltage Calculator.
Inputs for Total Harmonic Distortion
RMS of harmonic components and Fundamental RMS value belong to Total Harmonic Distortion. Keep source units with rms of harmonic components.
The sample case is a worked example, not a design target.
- RMS of harmonic components
- Example entry: 12 V.
- Fundamental RMS value
- Example entry: 230 V.
Reading the Total Harmonic Distortion result
This output represents Total Harmonic Distortion.
Component selection requires more than the arithmetic result; verify margins, transients, and published ratings.
Measurement and units
Use RMS quantities unless a field explicitly asks for peak amplitude. Check prefixes on rms of harmonic components.
Do not compare cases built from different unit prefixes or measurement locations.
Limits of this calculation
The harmonic input must exclude the fundamental component.
Only the stated inputs participate in this simplified model. Unentered effects remain outside Total Harmonic Distortion.
A useful Total Harmonic Distortion comparison
Save the initial total harmonic distortion before adjusting rMS of harmonic components. A low and high case is more informative than adding an unexplained safety factor after the calculation. Continue to Three-Phase Power Calculator for three-phase real power.
Document the alternate rms of harmonic components source.