How To Change Electrical Amps To Watts

Power is the rate at which work is performed. A watt is a measure of electromechanical power defined as one ampere, or amp, of current flowing through a circuit with an electrical difference of one volt. An amp is a measure of current equal to 1 coulomb of charge passing through a point in the circuit each second. The calculation of a circuit's wattage requires you to know the amperage and voltage of the circuit.

Step 1

Determine the voltage of the circuit. Assume for this example the circuit has 110 volts, the standard house voltage in the United States.

Step 2

Determine the amperage in the circuit. Assume for this example the circuit has a light bulb drawing about 0.91 amps.

Step 3

Multiply the number of amps by the number of volts to obtain the number of watts in the circuit. The equation W = A x V shows this relationship where W is the wattage, A is the amperage and V is the voltage. This example assumes a voltage of 110 volts and an amperage of 0.91 amps. The light bulb therefore uses 110 x 0.91 = 100 watts.