# Amps to watts calculator

Electric current in amps (A) to electric power in watts (W) calculator.

Select current type, enter current in amps,
voltage in volts,
power factor for AC circuit and press the *Calculate* button (DC = Direct Current, AC = Alternating Current):

* Use e for scientific notation. E.g: 5e3, 4e-8, 1.45e12

### DC amps to watts calculation

The power *P* in watts (W) is equal to the current *I* in amps (A), times the voltage *V* in volts (V):

*P*_{(W)} = *I*_{(A)}* *×* V*_{(V)}

## AC single phase amps to watts calculation

The power *P* in watts (W) is equal to the
power factor *PF* times the phase current *I* in amps (A), times the RMS voltage *V* in volts (V):

*P*_{(W)} = * PF *×* I*_{(A)}* *×* V*_{(V)}

## AC three phase amps to watts calculation

#### Calculation with line to line voltage

The power *P* in watts (W) is equal to square root of 3 times the power factor
*PF* times the phase current *I* in amps (A), times the
line to line RMS voltage *V*_{L-L} in volts (V):

*P*_{(W)} = *√*3
× * PF *×* I*_{(A)}* *×* V*_{L-L(V)}

#### Calculation with line to neutral voltage

The power *P* in watts (W) is equal to 3 times the
power factor *PF* times the phase current *I* in amps (A), times the line to neutral RMS voltage *V*_{L-N} in volts (V):

*P*_{(W)} = 3 × * PF *×* I*_{(A)}* *×* V*_{L-N(V)}

## Typical power factor values

Do not use typical power factor values for accurate calculations.

Device | Typical power factor |
---|---|

Resistive load | 1 |

Fluorecent lamp | 0.95 |

Incandescent lamp | 1 |

Induction motor full load | 0.85 |

Induction motor no load | 0.35 |

Resistive oven | 1 |

Synchronous motor | 0.9 |