Ohm's Law Calculator

Enter any two compatible values to calculate the remaining Ohm's law quantities instantly.

Voltage

Current

Resistance

Power

Enter any two known valuesV = IR · P = VI

—Voltage

—Current

—Resistance

—Power

For a simple resistive relationship. Real devices may be non-ohmic, temperature dependent, or frequency dependent.

Educational / low-voltage electronics calculator. Real components have tolerances and non-ideal behavior. Do not use this page as a substitute for qualified design or safety guidance for mains/high-energy electrical systems.

How to use this Ohm's Law Calculator

Solve voltage, current, resistance, and power from any two known electrical values. Enter your values above and the result is calculated directly in your browser. No account is required.

Fast answer, clear inputs

This tool is built around one job: give the answer quickly without forcing a signup or hiding the result. Related tools are linked nearby when the next calculation or conversion is useful.