Ohm's Law Calculator
Calculate voltage, current, resistance and power from two known electrical quantities.
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How to use this tool
- Select two known quantities and enter them in volts, amps, ohms or watts.
- Calculate the remaining values from Ohm's law and P = VI.
Things to know
- Uses positive DC or purely resistive values. Reactive AC impedance, power factor and component tolerances are excluded.
- Two positive finite numeric values of at most 120 characters. Fixed arithmetic produces four electrical quantities; nonfinite results are rejected.
- Use no more than 200,000 characters across the input and settings.
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