Maximum Power Transfer Calculator

How Maximum Power Transfer works

The calculation uses Rload = Rsource; Pmax = V² ÷ (4Rsource). Maximum Power Transfer uses Open-circuit voltage, Source resistance to report Matched load resistance.

With the loaded values, matched load resistance evaluates to 6.00 Ω. Change only the quantity being investigated.

Inputs for Maximum Power Transfer

Open-circuit voltage and Source resistance belong to Maximum Power Transfer. Keep source units with open-circuit voltage.

The preset case is instructional rather than prescriptive. Enter the applicable electrical data. For electric power, use Electric Power Calculator.

Open-circuit voltage

Example entry: 24 V.

Source resistance

Example entry: 6 Ω.

Reading the Maximum Power Transfer result

This output represents Maximum Power Transfer. If the next question concerns shunt resistance, open Shunt Resistor Calculator.

Finish the selection with standard sizes, operating limits, and transient review.

Measurement and units

Use measured values and keep prefixes such as milli, kilo, and mega consistent before calculating. Check prefixes on open-circuit voltage.

Keep the same electrical reference points across saved cases.

Limits of this calculation

Maximum power transfer operates at only fifty percent source efficiency.

A complete system can contain effects that this equation does not represent. Unentered effects remain outside Maximum Power Transfer. Use Material Resistivity Calculator as the follow-up for resistivity.

A useful Maximum Power Transfer comparison

Record matched load resistance before testing a different open-circuit voltage value. Loaded output voltage belongs in the separate Loaded Voltage Divider worksheet.

Document the alternate open-circuit voltage source.

Questions about Maximum Power Transfer