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Ohm's Law Calculator

Enter any two of voltage, current, resistance and power to get the other two using Ohm's law and the power formula.

Voltage (V) (0 = unknown)

Current (A) (0 = unknown)

Resistance (Ω) (0 = unknown)

Power (W) (0 = unknown)

How to use it

Fill in any two values and set the unknowns to 0.

How it works

V = I × R, P = V × I = I²R = V²/R.

FAQ

What is Ohm's law?

Voltage equals current times resistance (V = I × R).

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