How do you calculate watts from volts and amps?
Multiply volts by amps. The formula is P = V x I, where P is power in watts, V is voltage in volts, and I is current in amps.
Calculate electrical power in watts from voltage and current. See the P = V x I formula with a worked volts-and-amps example.
Power
1200.00W
P = V * I
Enter voltage in volts and current in amps to calculate electrical power in watts. This calculator uses the direct-current and resistive-load relationship P = V x I.
P = V * I
A 120-volt device drawing 10 amps uses 1,200 watts because 120 x 10 = 1,200.
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Multiply volts by amps. The formula is P = V x I, where P is power in watts, V is voltage in volts, and I is current in amps.
The result is 1,200 watts: 120 volts multiplied by 10 amps.
Yes for many AC loads. This calculator uses P = V x I and does not apply a power-factor adjustment, so use the result as apparent input power unless the load is resistive or power factor is 1.