Science & Engineering

Electrical Power Solver (Ohm & Joule Laws)

Find power, voltage, current, or resistance from any valid pair using Ohm's and Joule's laws. It returns watts, kilowatts, horsepower, energy, and running cost.

How to use
  1. Pick the input mode for the two values you know.
  2. Enter those two values.
  3. Check the energy and cost figures.
For study and estimation. Verify against authoritative data before relying on a result.
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Common questions

What is the basic power formula?

Power equals voltage times current, and it can also be written as current squared times resistance or voltage squared divided by resistance.

How is energy cost worked out?

Multiply the power in kilowatts by the hours of use to get kWh, then multiply by your electricity rate.

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