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Watt conversion calculator

The Watt is a unit of measurement used to measure the power consumption of smaller home appliances, such as toasters, kettles, irons, computer monitors, and printers.

Understanding what a Watt is can help you reduce your electricity usage and bill.

What is a Watt

Watt (W) is a unit used to measure power.

And a Watt is the amount of energy our household appliances and devices need to function, the rate at which they consume energy.

One watt is equivalent to electricity flowing at one joule per second.

For example, a light bulb rated at 60 W will need that much power to produce a predetermined amount of light (lumens).

light bulb lumen and watts comparison table

The following YouTube video explains what a watt is and how it relates to other power measurement units and our household appliances and devices.

Do not forget to enable the video captions, as the video caption contains the concepts and explanations.

What is a Kilowatt hour (kWh)

Conversion calculator to convert Watts to other units

Watt (W) to Kilowatt (kW) conversion calculator

To convert Watts (W) to Kilowatts (kW), you must divide the Watts by 1000.

kW = W/1000


For example, if a device uses 300 Watts, but we need to know how much that is in Kilowatts:

300/1000 = 0.3 kW 

Watt (W) to Kilowatt hour (kWh) conversion calculator

To convert Watts (W) to Kilowatt hours (kWh), you need to divide the number of Watts by 1000 and multiply the result by the number of hours.

kWh = (W/1000) x Hours

kWh is the measurement unit the electricity suppliers use to calculate our electricity bills. 

Also, most big appliances, like dishwashers or washing machines, rate their consumption in kWh.


For example, if a device uses 300 Watts and has been in use for 5 hours:

(300/1000) = 0.3 kW

0.3 kW x 5 hours = 1.5 kWh 

Watt cost calculator

The electricity cost is calculated based on the number of Kilowatt hours (kWh) an appliance, device, or household uses.

Still, if you need to know how much you pay per Watt (W) or, more specifically, per Watt-hour (Wh), you need to divide how much you pay per kWh by 1000.


If you don’t know how much you are paying per kWh, you should be able to find the cost per kWh on your electricity contract or in one of the electricity bills.

For example, the user from the picture below is paying 31,90 cents per kWh.

Nowadays, it is very common that the electricity contract details, the monthly or yearly electricity usage, and electricity cost can be accessed online.

how much does electricity cost

Alternatively, if you don’t have access to your contract or your electricity bills, this website does show the electricity cost per country.

Watts-hour (Wh) to Amps-hour (Ah) conversion calculator

To convert Watts-hour (Wh) to Amps-hour (Ah), you must divide the Watts-hour by voltage.

Ah = Wh/V


For example, if a device uses 350 Watts per hour in a country where the power supply is 220 Volts:

350 Wh / 220 V = 1.591 Ah

Watt (W) to Amp (A) conversion calculator

To convert Watts-hour (Wh) to Amps-hour (Ah), you must divide the Watts-hour by voltage.

A = W/V


For example, if a device uses 350 Watts in a country were the power supply is 220 Volts:

350 W / 220 V = 1.591 A

Here are a few other examples from our ‘Electricity usage and electricity cost calculators‘ page that may be of your interest:

Watt electricity usage monitor

If you want to know how many watts an appliance or device uses, your best option is to use a plug-in power meter to measure the electricity consumption. 

Clicking on the image below will redirect you to the Amazon page, where you can look at the specifications of the power meter we use for our measurements.

plug in power meter

Our house appliances and devices like the washing machine, the dishwasher, the TV, or the printer are plugged into a wall socket. 

So, with a power consumption meter, we can determine how much electricity our appliances or devices are using, and, more importantly, we can measure the electricity usage over time.

If you want to find out how to use a plug-in power meter to measure your electricity usage and electricity cost, look at this YouTube video.

Plug in power meter

Watt FAQ

How many watts is a kilowatt?

A kilowatt is equal to 1000 watts.

How much is a kilowatt of electricity?

It depends on the contest.

In terms of money, the cost of a kilowatt hour depends on where you live or even the contract you have with the electricity provider. For example, in Germany in 2021, the average cost per kilowatt hour is 33 cents.

In terms of quantity, a small electric fan uses around 50 Watts an hour, so it will take 20 hours to use one kilowatt.

Instead, an air conditioner can use around 1500 Watts an hour, so using one kilowatt will take less than one hour.

Watt and energy conservation

Energy conservation can be defined as the decision and the act of using less energy.

Energy conservation both benefit you and the environment

The act of saving and conserving electricity does benefit you because you will be paying less for your energy bills. 

And it also benefits the environment because conserving electricity prevents unnecessary waste of natural resources.

At the individual level, it may not look worth trying to save a few watts here or there. 

Still, every little one counts, and if hundreds or thousands of us save a little every time, it will make an important contribution towards conserving our natural resources.


For example, if 9000 households save as little as 10 Watts per day (0,01 kWh), that would save 32850 Kilowatt hours (kWh) annually. 

9000 households x 0,01 kWh per day x 365 days per year 

32,850 kWh saved per year

That is a considerable amount of electricity, but let’s add additional perspectives for clarity:

> Assuming an average cost of 0,18 euros (or dollars, pounds, or any other currency) per kWh, we would collectively save nearly 6000 euros annually.

> To produce 32,850 kWh of electricity, it is necessary to use around 17 metric tons of coal or 56 barrels of residual fuel oil.

Look at this page for more information about the resources needed to produce electricity.

In any case, small energy savings do count when looking into the bigger picture.

Proven ways to save electricity at home

Suppose you are looking for ideas to save electricity at home; look at this YouTube video. We show some useful tips for reducing electricity usage at home and decreasing the electricity bill. 

How to save electricity at home
How to save
How to save
How to earn
How to earn


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