# Watt (W)

- Watt definition
- Watt to mW, kW, MW, GW, dBm, dBW conversion calculator
- Table of unit prefixes of watt
- How to convert watts to kilowatts
- How to convert watts to milliwatts
- How to convert watts to dBm
- How to convert watts to amps
- How to convert watts to volts
- How to convert watts to ohms
- How to convert watts to btu
- How to convert watts to joules
- How to convert watts to horsepower
- How to convert watts to kVA
- How to convert watts to VA
- Power consumption table

## Watt definition

Watt is the unit of power (symbol: W).

The watt unit is named after James Watt, the inventor of the steam engine.

One watt is defined as the energy consumption rate of one joule per second.

1W = 1J / 1s

One watt is also defined as the current flow of one ampere with voltage of one volt.

1W = 1V × 1A

## Watt to mW, kW, MW, GW, dBm, dBW conversion calculator

Convert watt to milliwatt, kilowatt, megawatt, gigawatt, dBm, dBW.

Enter the power in one of the text boxes and press the *Convert* button:

## Table of unit prefixes of watt

name | symbol | conversion | example |
---|---|---|---|

picowatt | pW | 1pW = 10^{-12 }W |
P_{ }= 10 pW |

nanowatt | nW | 1nW = 10^{-9 }W |
P_{ }= 10 nW |

microwatt | μW | 1μW = 10^{-6 }W |
P_{ }= 10 μW |

milliwatt | mW | 1mW = 10^{-3 }W |
P = 10 mW |

watt | W | - | P = 10 W |

kilowatt | kW | 1kW = 10^{3 }W |
P_{ }= 2 kW |

megawatt | MW | 1MW = 10^{6 }W |
P_{ }= 5 MW |

gigawatt | GW | 1GW = 10^{9 }W |
P_{ }= 5 GW |

### How to convert watts to kilowatts

The power P in kilowatts (kW) is equal to the power P in watts (W) divided by 1000:

*P*_{(kW)} = *P*_{(W)} / 1000

### How to convert watts to milliwatts

The power P in milliwatts (mW) is equal to the power P in watts (W) times 1000:

*P*_{(mW)} = *P*_{(W)} · 1000

### How to convert watts to dBm

The power P in decibel-milliwatts (dBm) is equal to 10 times base 10 logarithm of the power P in milliwatts (mW) divided by 1 milliwatt:

*P*_{(dBm)} = 10 · log_{10}( *P*_{(mW)} / 1mW)

### How to convert watts to amps

The current I in ampers (A) is equal to the power P in watts (W) divided by the voltage V in volts (V):

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

### How to convert watts to volts

The voltage V in volts (V) is equal to the power P in watts (W) divided by the current I in ampers (A):

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

### How to convert watts to ohms

*R*_{(Ω)} = *P*_{(W) }*/ I*_{(A)}^{2}

*R*_{(Ω)} = *V*_{(V)}^{2}/* P*_{(W)}

### How to convert watts to btu/hr

*P*_{(BTU/hr)} = 3.412142 · *P*_{(W)}

### How to convert watts to joules

*E*_{(J)} = *P*_{(W)} · *t*_{(s)}

### How to convert watts to horsepower

*P*_{(HP)} = *P*_{(W) }/ 746

### How to convert watts to kVA

The real power P in watts (W) is equal to 1000 times the apparent power S in kilo-volt-amperes (kVA) times the power factor (PF) or cosine of the phase angle φ:

*P*_{(W)} = 1000 · S_{(kVA)} · *PF* = 1000 · *S*_{(kVA)} · cos *φ*

### How to convert watts to VA

The real power P in watts (W) is equal to the apparent power S in volt-amperes (VA) times the power factor (PF) or cosine of the phase angle φ:

*P*_{(W)} = *S*_{(VA)} · *PF* = *S*_{(VA)} · cos *φ*

## Power consumption of some electrical components

How many watts does a house use? How many watts does a TV use? How many watts does a refrigerator use?

Electric component | Typical power consumption in watts |
---|---|

LCD TV | 30..300 W |

LCD monitor | 30..45 W |

PC desktop computer | 300..400 W |

Laptop computer | 40..60 W |

Refrigerator | 150..300 W (when active) |

Light bulb | 25..100 W |

Fluorescent light | 15..60 W |

Halogen light | 30..80 W |

Speaker | 10..300 W |

Microwave | 100..1000 W |

Air conditioner | 1..2 kW |

## See also

- Electric power
- Decibel-milliwatt (dBm)
- Decibel-watt (dBW)
- Kilowatt (kW)
- Kilowatt-hour (kWh)
- Volt (V)
- Ampere (amps)
- Ohm
- Ohm's law
- Power conversion
- Watts to kW conversion
- Watts to mW conversion
- Watts to dBm conversion
- Watts to Horsepower conversion
- Watts to BTU/hr conversion
- Energy conversion
- Watts to Amps calculation
- Watts to Joules calculation
- Watts to Volts calculation
- Electrical units