Motor efficiency calculator

Efficiency compares mechanical output with electric real input.

\eta = \frac{P_{\text{shaft}}}{P_{\text{input}}}

Calculator

Enter the values you know and leave one box empty. Calculate finds the empty one, the result or any input.

Given

\eta = \frac{37.3}{40.5} \approx 0.921

Symbol	Meaning	Unit
$\eta$	motor efficiency as fraction	—
$P_{\text{shaft}}$	mechanical shaft output	kW
$P_{\text{input}}$	electrical real input	kW

Results are estimates for study and screening. Check the inputs, units and assumptions before you use them for design, billing or contract decisions.