Ohm’s law, AC current and energy cost

Find voltage, current, resistance and power from any two known DC values. Estimate single-phase or balanced three-phase AC current and electricity use.

Ohm’s law mode assumes a resistive DC load. AC mode uses active electrical input power in watts and power factor; three-phase voltage is line-to-line and the load must be balanced.

Calculation mode

Two known values

Voltage, V

Resistance, Ω

Operating time, h

Price per kWh

Currency or cost unit (optional)

This is an educational calculation, not cable, breaker or wiring selection. It does not account for harmonics, inrush current or motor efficiency. Energy cost assumes constant power for the entered operating hours.

Quick start

Ohm’s law, AC current and energy cost

Enter the source data and check its units.
Run the calculation or conversion and wait for completion.
Review the report or file and download the result.

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Ohm’s law, AC current and energy cost