Enter the total power in Watts, and the total time to calculate the equivalent KWH (Kilowatt-hours).

## What is KWH?

KWH is short for kilowatt hour, which is a unit of measure of energy that is eqaul to 3.6 megajoules. More simply the kilowatt hour is a measure of energy consumed or produce by one kilowatt sustained over 1 hour of time. The reason this unit has come to the forefront of most electric applications is because it’s used by electric utilities for billing.

A watt is a measure of power, and hours is a measure of time. Multiply power by times yields energy, and that’s why KWH is considered a derived unit of energy. It’s not officially recognized by the SI unit system, although the derived unit of joules is.

## KWH Formula

The following formula is used to calculate KWH:

KWH = Watts/1000*hours

The formula can also be simplified to simply KW*hours. THE KWH formula is one of the easiest to remember. This is because the formula itself is written into the name KWH.

## How to calculate KWH

Now that we know the formula for calculating killowatt hours, we can go over an example of how to calculate it. Let’s take an example of trying to calculate the KWH usage of a light bulb.

- First, you need to determine the total power consumption of the light bulb. For light bulbs this is almost always shown directly on the package in watts. For our example we will assume a standard 250 watt light bulb.
- Next, you need to determine how long the light bulb will run for. This could be over it’s life time, or over a shorter period like a day. For this we will calculate the KWH usage for one day = 24hours.
- Last, enter the information into the formula or calculator above.
- KWH = 250/1000*24= 6 KWH.
- To use this information in a useful way, multiply that number by the cost of electricity in your home per KWH and you know the cost of running that light bulb for 1 day.

Similarly, we can do this for any appliance that uses electricity. This can be extremely helpful in determining your estimated electric bill. Let’s take a look at an example of an air conditioning unit.

- First, determine the power usage of the air conditioning. And average central air unit likely runs at approximately 3500 watts. A window unit likely runs closer to 500-1000 watts or less. We will assume ours is a central air unit.
- Next, determine how long it will run for. We will assume a period of 7 days running 16 hours per day = 112 total hours.
- Enter the hours and power into the formula to calculate KWH.
- KWH = 3500/100*112 = 392 KWH.
- Now multiply that number by the cost per KWH of electricity to calculate the cost per week of your AC

## KWH Usage in Cars

The term Kilowatt hours has become more and more prevalent over the last 5-10 years, and that’s mostly due to one thing…cars. More specifically, electric cars. Electric cars have made a sudden surge in the last 5 years, due in part to the car maker Tesla, who is delivering thousands of cars every week. Electric cars are starting to appear more and more and you guessed it, they run on electricity. And what term is used with electricity? You guessed it, KWH.

In the same way that appliances use electricity, so do electric cars. Cars consume electricity in the form of power from batteries stored on the under carriage. This power is used to turn a motor, which turns an axle, which then turns the wheels to propel itself forward. Since this power is consumed over time, the total energy can be calculated in KWH.

The KWH of an electric car is usually specified as a metric to show off the power of a car, but in terms of range it does not mean much. An electric car with a lower KWH could still drive much further. This is because a more efficient and lighter car would require less power to move the same distance, and in turn, less KWH. This is very important to keep in mind when purchasing an electric car.

For more science and physics calculators, click here.

## Related Terms

kwh calculator |

kwh formula |

how to calculate kwh |

household electricity consumption calculator |

electricity usage calculator |

kilowatt calculator |

convert watts to kilowatts |

how to calculate electricity consumption |

kilowatt formula |

how to calculate maximum demand from kwh |

how to calculate kwh from amps |

how to find kwh |

watt cost calculator |

convert kilowatts to amps |

calculate electricity consumption |

convert kilowatts to watts |

how to calculate electricity usage |

kwh formula 3 phase |

kwh usage calculator |

electricity cost calculator kwh |

how to calculate kilowatts |

how to convert kilowatts to watts |

how to convert watt into kilowatt |

watt to kilowatt conversion |

joules to kwh formula |

kilowatt conversion |

how to calculate the cost of electricity |

volts to kilowatts conversion calculator |

kilowatts to amps calculator |

kwh calc |

electricity bill calculator kwh |

estimate electricity usage |

3 phase kwh meter calculation |

electrical energy formula kwh |

energy calculator kwh |

power consumption calculator kwh excel |

convert amps to kilowatts |

how many amps in 1 kw |

cost of electricity formula |

convert amps to kwh |

electricity kwh calculator |

energy meter constant formula |

calculate the electrical energy consumed by a 1200w toaster in 30 minutes |

how to convert kilowatt into watt |

convert kilowatt to kva |

kilowatt equation |

how to convert kilowatts to amps |

kwh to kcal conversion formula |

computer kwh |

kilowatt to amp conversion |

1 kw to kva calculator |

kilowatt cost calculator |

1kwh to unit conversion |

convert watt into kilowatt |

amps to kilowatts calculator |

how do you convert watts to kilowatts |

electric power consumption calculator |

ampere to kwh formula |

1 kw is equal to how many amps |

how to figure kwh |

kwh estimator |

how to calculate electricity cost from watts |

kilowatts to watts conversion |

electricity cost calculator watts |

1 kw is equal to how many volts |

estimate kwh usage |

how to determine kwh |

mw to kwh calculator |

how to calculate kwh usage |

power consumption calculator kwh |

how to calculate electricity cost per kwh |

how to calculate kwh from meter reading |

kilowatt to ampere formula |

kilowatt usage calculator |

kwh to mw calculator |

kj to kwh formula |

calculate cost of electricity per kwh |

kwh to joules formula |

kwh meter reading calculator |

how to convert amps to kilowatts |

kilowatt to unit conversion |

kva to kwh conversion |

pc kwh calculator |

kwh ampere calculator |

how to calculate kwh price |

kilowatt to horsepower calculator |

3 phase kwh calculator |

kwh per square foot calculator |

kwh rate calculator |

how to calculate electrical energy consumption |

single phase energy meter constant formula |

annual energy consumption calculator |

kj to kwh conversion calculator |

watt to kilowatt calculator |

how to convert kilowatt to watt |

how to figure kilowatts |

convert volts to kilowatts |

appliance kwh calculator |

kilowatt to kva formula |

kwh to php |

kwh calculator for home |

kwh bill calculator |

kilowatt to horsepower formula |

horsepower to kwh conversion |

find kwh |

electricity kilowatt calculator |

kilowatt to hp formula |

electrical energy consumption formula |

watts to kilowatts conversion calculator |

kilowatt to horsepower conversion calculator |

ampere to kilowatt formula |

how do you calculate kwh from your electricity meter |

how to convert ampere to kilowatt |

household power consumption calculator |

meter constant of energy meter formula |

electricity cost per unit calculator |

1 kwh to php |

how to calculate kilowatts from amps |

how to convert kilowatt to kva |

kilowatt to ampere calculator |

formula kilowatt |

how to calculate kwh in 3 phase |

cost of electrical energy consumption |

price per kwh calculator |

convert 1 kw to kva |

kva to kwh calculator |

annual kwh calculator |

kilowatt calculator home |

electricity usage cost calculator |

how many btu in kwh |

energy in kwh formula |

kwh convert to kva |

kilowatt to ampere conversion formula |

how to calculate the cost of electrical energy consumed |

how to convert kwh to amps |

joules to kwh calculator |

how many amps are in 1 kw |

how to convert kilowatt to ampere |

kva to kwh converter |

watts to kilowatts formula |

energy cost calculator kwh |

how to get kwh from meter reading |

3 phase electricity cost per kwh |

convert kva to kilowatt |

kwh to dollar calculator |

how to calculate kwh from hp |

how to calculate solar panel kwh |

kwh to gwh calculator |

how to convert from watts to kilowatts |

how to find cost of electricity |

cost of electricity formula physics |

electricity usage calculator cost |

generator kwh calculation |

how to determine how many kwh you use |

kilowatt ampere calculator |

how to calculate energy consumption in kwh |

calculate kwh from volts and amps |

kcal to kwh calculator |

kilowatt calculation formula |

estimate my electricity usage |

estimated annual electricity use |

kwh to joules calculator |

how do you calculate the cost of electricity |

kilowatt to joules calculator |

annual electricity consumption calculator |

horsepower to kilowatts conversion calculator |

calculate my electricity usage |

pool pump kwh calculator |

calculate the electric energy consumed by a 1200 w toaster in 20 minutes |

electricity kwh usage calculator |

kilowatt formula three phase |

kilowatts to watts calculator |

kwh charge calculator |

calculate kwh battery pack |

how to calculate energy in kwh |

motor kilowatt calculator |

how do you calculate kilowatts |

hp to kilowatt calculator |

daily electricity consumption calculator |

daily electricity usage calculator |

computer kwh usage |

how to convert amps to kwh |

how to determine kwh usage |

kwh to kva converter |

how to calculate kwh from amps and volts |

how to calculate electric power consumption |

power cost calculator watts |

3 phase kilowatt calculator |

energia kwh formula |

how to calculate how many kwh an appliance uses |

convert kwh to horsepower |

how do you convert kilowatts to watts |

5 kilowatts to amps |

conversion from watt to kilowatt |

electrical energy cost calculator |

how to determine electricity usage |

kilowatt to hp conversion formula |

convert kj to kwh formula |

horsepower to kilowatt calculator |

how to calculate kva from kwh |

watt to kilowatt conversion calculator |

conversion of watt into kilowatt |

how to calculate electric bill kwh |

hp to kilowatt formula |

how to calculate the amount of electricity used |

kwh to amp converter |

convert kwh to gj calculator |

how to calculate cost of electricity physics |

joule kwh unit conversion |

how to calculate amps to kwh |

kwh to pounds calculator |

energy bill calculator kwh |

how to calculate electricity usage from meter reading |

how do i calculate kwh from my meter reading |

how to calculate kilowatt to ampere |

kilowatt ampere conversion |

megawatt to kilowatt calculator |

home electricity usage calculator |

how to calculate electricity consumption of a device |

how to calculate electricity usage of an appliance |

amps to kilowatt conversion |

how to calculate kwh from amps 3 phase |

average electricity usage calculator |

calculate electricity usage from meter reading |

how to calculate kwh from electric bill |

dg kwh calculation |

how to calculate energy meter constant |

how to convert kilowatts into watts |

calculate kwh from amps and voltage |

kwh reading formula |

kilowatt consumption calculator |

calculate the approximate quantity of kwh of a geyser |

how to convert kilowatts into amps |

conversion of ampere to kilowatt |

how to calculate cost of electricity usage |

how to calculate the usage of electricity |

convert kwh to volts |

how to calculate amount of electricity used |

how to calculate the cost of energy |

calculator kwh in lei |

power in kilowatts formula |

3 phase motor kwh calculator |

kilowatts to watts conversion calculator |

convert watts to kilowatts calculator |

how to find out how many kwh i use |

how to calculate daily electricity consumption |

watt to kilowatt converter online |

convert kilowatts to volts |

how do i calculate electricity usage |

convert volts to kwh |

how do i calculate my electricity usage |

how to calculate my kwh usage |

how to find cost per kwh |

how to convert kilowatts to kva |

kilowatt to volt converter |

how to count electricity usage |

joule kwh calculator |

kwh to kj formula |

meter reading kwh calculator |