Ohm's Law Calculator

Enter any two known values. The rest are calculated instantly.

Fill in exactly 2 fields. Leave the others blank.

⚡ Voltage (V)

🔌 Current (A)

Ω Resistance (Ω)

💡 Power (W)

⚡

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Volts (V)

🔌

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Amps (A)

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Ohms (Ω)

💡

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Watts (W)

Ohm's Law Reference

V = I × R — Voltage = Current × Resistance

I = V / R — Current = Voltage / Resistance

R = V / I — Resistance = Voltage / Current

P = V × I — Power = Voltage × Current

P = I² × R — Power = Current² × Resistance

P = V² / R — Power = Voltage² / Resistance

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