Watts to Amps Calculator

Last Updated on October 8, 2026

You may keep asking in your mind that how much current will this load draw? whenever you see a electronic appliance or electrical equipment. The lable on a device usually give the power in Watts or KiloWatts that is KW. But the wire, fuse, MCB and power supply are all in between that device and power line, using amps. So you need a quick and reliable way to convert Watts to Amps.

Here is what you are looking for, a Watts to Amps Calculator from theorycircuit, It also works as a kW to Amps calculator, and it can find the power in watts when you know the voltage and current (the volts to watts calculation). This calculator supports DC supply calculation, Single phase AC supply and three phase AC supply and it accepts power factor and efficiency so that the answer is close to what you will measure.

Watts to Amps Calculator

Calculate:

Supply Type:

Power (P):

Voltage (V):

Current (I):

Power Factor:

Efficiency (%):

Result:

Enter the values above and click Calculate.

Watts to Amps Calculator Formula

Here this calculator works based on the following formula for watts to amps conversion.
The formula depends on the type of supply. Here P is power in watts, V is voltage in volts, I is current in amps, PF is the power factor and η is efficiency noted in decimal example 90% is 0.9 like that.

Power Supply	Watts to Amps	Volts and Amps to Watts
DC	I = P ÷ V	P = V × I
AC Single Phase	I = P ÷ (V × PF)	P = V × I × PF
AC Three Phase	I = P ÷ (√3 × V × PF)	P = √3 × V × I × PF

Here the Watts tell you how much power a load uses, but amps decide the size of the wire then the rating of the fuse and the capacity of the power supply. Converting between them is simple once you know the supply type and the power factor. Use this watts to amps calculator whenever you need a quick answer for a DC circuit or a home appliance power calculation or for to calculate watts of three phase motor etc.,