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Electrical

Maximum Power Transfer Calculator

Find the matched resistive load and maximum load power for a Thevenin source.

Ideal component relationshipsUnits and assumptions explained below
Circuit workbench
Circuit workbench

Keep RMS, peak and DC values distinct.

See the method

Enter circuit values

Runs on your device

Your circuit result

Your result

Let’s calculate.

Use the Calculate button to see your result.

Review the method below for assumptions and conventions.

How to use this tool

  1. Enter thevenin voltage, thevenin resistance.
  2. Select Calculate to view the result.
  3. Check the method and assumptions below before using the result.

The method, explained

For positive source resistance, maximum load power occurs at RL=Rth and equals Vth²/(4Rth).

A WORKED EXAMPLE

Using thevenin voltage = 12 V, thevenin resistance = 50 Ω, the result is 0.72 W. Change these example inputs to match your task; use the method above to check each step.

Understanding your result

Resistive DC matching; it maximizes delivered power rather than efficiency. Does not address RF impedance matching or ratings.

What to keep in mind

Resistive DC matching; it maximizes delivered power rather than efficiency. Does not address RF impedance matching or ratings. Ideal-component calculation for study and estimation. It does not select safe wiring, protective devices or component ratings for an installation.

Common questions

How do I use this maximum power transfer calculator?

Find the matched resistive load and maximum load power for a Thevenin source. Enter thevenin voltage in V, thevenin resistance in Ω. The starting example is editable; use values for the same system or project.

Which assumptions affect this result?

Resistive DC matching; it maximizes delivered power rather than efficiency. Does not address RF impedance matching or ratings.

Methodology maintained by ClarityKit. How these tools are built and checked.