How to use the efficiency calculator
Find efficiency and wasted energy from input and output. Enter input power or energy, useful output in the fields above; the efficiency, wasted energy or power are computed instantly and plotted on the chart so you can see how the answer changes.
Formula
Variables
- Pin — Input power or energy
- Pout — Useful output
Worked example
With input power or energy = 1000, useful output = 750, the calculator gives efficiency ≈ 75 %; wasted energy or power ≈ 250.
Frequently asked questions
What is the formula for the efficiency calculation?
Efficiency (%) = 100 × Pout / Pin. Wasted energy or power = Pin-Pout. Here Pin is input power or energy, Pout is useful output.
What inputs do I need for the efficiency calculator?
You need input power or energy, useful output. Each field is pre-filled with a typical example so you can see how the result responds as you edit the numbers.
How do I use this calculator?
Type values into the input fields. Results and the chart update instantly. Use Reset to restore the example values, Copy results to paste them elsewhere, or Share to copy a link that preserves your inputs.
Is the result exact?
Calculations use standard formulas and double-precision arithmetic, then display about seven significant figures. Real-world measurements carry uncertainty, so treat results as estimates unless your inputs are exact.