Power converter

Volts to Watts Calculator

Calculate electrical power in watts from voltage and current in amps.

How Volts to Watts works

Volts measure electrical potential force, while watts measure actual energy output. To convert volts to watts, you must also know the current in amps running through the circuit.

Multiply volts by amps to determine the electrical power in watts (P = V × I). For AC loads, you also account for the power factor (PF) of the system.

Formula

1P(W) = V(V) × I(A) (DC)DC

2P(W) = V(V) × I(A) × PF (AC single phase)1Φ

3P(W) = V(V) × I(A) × PF × √3 (AC three phase)3Φ

1 watt is 1 volt at 1 amp of current.

Volts to Watts conversion table

Reference Table6 rows

Volts to watts at common currents (DC / resistive, PF = 1.0).
Voltage (Volts)↕	At 1 A↕	At 10 A↕	At 15 A↕
12 V	12 W	120 W	180 W
24 V	24 W	240 W	360 W
120 V	120 W	1,200 W	1,800 W
208 V	208 W	2,080 W	3,120 W
240 V	240 W	2,400 W	3,600 W
480 V	480 W	4,800 W	7,200 W

💡 Click any row to auto-fill the calculator aboveClick column headers to sort

FAQ: Volts to Watts

How do you convert volts to watts?

Multiply the voltage in volts by the current in amps. Watts = Volts × Amps. For alternating current (AC) systems, also multiply by the power factor.

Are volts and watts the same thing?

No. Volts measure the pressure of electrical current, whereas watts measure the overall power (energy flow rate). An appliance can have high voltage but draw very low power if the current is extremely small.

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