Watts to Amps Calculator
Convert watts to amps (and amps to watts) for DC, single-phase AC, and three-phase AC circuits. Essential for sizing breakers, wiring, and electrical panels. Enter your values and get instant, accurate results.
Enter Electrical Values
Full Breakdown
Power
Voltage
Circuit Type
Power Factor
Current
Suggested Breaker
How to Use This Calculator
- Choose conversion direction — watts to amps or amps to watts.
- Select the circuit type — DC, single-phase AC, or three-phase AC.
- Enter power (watts) and voltage.
- For AC circuits, select the power factor (0.85 is a safe default).
- Click "Calculate" for instant results with breaker recommendations.
The Formulas
DC: Amps = Watts ÷ Volts
AC Single-Phase: Amps = Watts ÷ (Volts × Power Factor)
AC Three-Phase: Amps = Watts ÷ (Volts × √3 × Power Factor)
Power factor (PF) accounts for the phase difference between voltage and current in AC circuits. Resistive loads (heaters, incandescent bulbs) have PF = 1.0. Motors and inductive loads typically have PF between 0.8 and 0.95.