Total Harmonic Distortion (THD) Calculator

Quantify harmonic distortion by entering individual harmonic magnitudes. Automatically checks against IEEE 519 THD limits.

Total Harmonic Distortion (THD)

Enter harmonic amplitudes as percentages of the fundamental frequency. Leave unused orders at 0.

Fundamental (1st) Amplitude

3rd Harmonic (%)

5th Harmonic (%)

7th Harmonic (%)

11th Harmonic (%)

13th Harmonic (%)

Sum of all other harmonics (%)

Total Harmonic Distortion (THD)30.5%

THD (%):30.5%

IEEE 519 Limit (≤ 5% for most systems):⚠ EXCEEDS limit

RMS including harmonics:—

Dominant Harmonic:5th

FormulaTHD = √(V₂²+V₃²+…) / V₁ × 100%