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Volts to Watts Calculator
Enter voltage and current to get power in watts.
Power
—
Watts.
| Kilowatts | — |
|---|---|
| Voltage | — |
| Current | — |
| — |
Show our math
Enter your figures above to see the step-by-step working.
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How the Volts to Watts Calculator Works
Watts, the unit of electrical power, equal volts times amps: P = V × I. So a device on 120 volts drawing 5 amps uses 600 watts. Voltage alone doesn’t give power — you also need the current, because power is how fast energy is used, and that depends on both.
For DC and simple resistive AC loads this is exact. For reactive AC loads (motors, some electronics) real power also involves the power factor.
watts = volts × amps
Frequently Asked Questions
How do you convert volts to watts?
Multiply the voltage by the current in amps. 120 V × 5 A = 600 W.
Can you get watts from volts alone?
No — you also need the current (amps) or the resistance, because power depends on both voltage and current.
What is the formula for electrical power?
P = V × I (watts = volts × amps). It can also be written I²R or V²/R.
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