Watts to amps converter
Convert watts to amps and amps to watts for 127 V, 220 V or any voltage circuit, single-phase or three-phase, with power factor.
How to useWatts to amps (and amps to watts)
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Watts to amps converter: what it is for
Choose the direction of the conversion, enter the voltage, the power factor and whether the system is single-phase or three-phase. The converter shows the current in amps or the power in watts and kilowatts, plus the apparent power in kVA.
How to use
- Choose watts to amps or the reverse.
- Enter the voltage and the power factor.
- Read the result.
When to use it
- Finding the current of a shower heater.
- Choosing a 10 A or 20 A outlet.
- Sizing a generator or UPS.
Frequently asked questions
How do I convert watts to amps?
Divide the power by the voltage: I = P ÷ V. A 5,500 W shower heater at 220 V draws 25 A; the same heater at 127 V would draw 43.3 A. For motors and appliances with a power factor, also divide by the factor.
What about three-phase?
In balanced three-phase circuits, the current is P ÷ (√3 × V × PF), using the line-to-line voltage, such as 220 V or 380 V.
What is power factor?
It is the share of apparent power that becomes useful work. Resistive loads like a shower heater or an iron have a factor of 1; motors and power supplies generally fall between 0.8 and 0.95.
Is it really free?
Yes, 100% free. No sign-up, no subscription and no usage limits. All Tools123 are free.