Dev Utilities

Ohm's Law Calculator

Enter any two of voltage, current, and resistance to calculate the third using Ohm’s Law (V = I x R), plus the resulting power in watts. A quick reference for basic electronics and circuit calculations.

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Frequently asked questions

What is Ohm’s Law?

A fundamental electronics relationship stating that voltage equals current multiplied by resistance, for simple resistive circuits.

How is power calculated?

Power in watts equals voltage multiplied by current, calculated automatically once voltage and current are known.

Does this account for AC circuits with reactance?

No, this calculates basic DC (or simple resistive) Ohm’s Law relationships only.

Calculate Ohm’s Law instantly - free.

Open Ohm's Law Calculator
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