How Many Watts Does it Take to Run A Microwave?

A microwave oven is a very practical appliance: it can cook some simple foods (no meats, please) and can reheat your leftovers. However, the energy consumption of a microwave oven is not low, so it is important to know how much power most microwaves use. A countertop microwave uses less power than a build-in large oven, but how much exactly and how much it costs to run is yet to be seen. Let’s learn more. 

What is a Microwave Wattage?

Simply put, a microwave wattage is how many watts does a microwave use when it is running. Although microwave ovens are very different from one another, it is simple to categorize them based on their energy consumption. You can find information on your microwave wattage on the backside, where the energy information label is. Most residential microwaves use 600-1,000 Wh, but a commercial oven can easily use more than 1,000 Wh. 

How Many Watts Does a Microwave Use?

How many watts a microwave uses depends on the model, energy efficiency rating, and how often it is used. A microwave oven used for 5 minutes a day uses less power than a restaurant oven running 2-3 hours a day. Most microwaves on the market fall into one of the following categories based on their energy consumption: 

1. Compact microwave – uses 600-800 Wh – these are small, countertop microwave models. This type of microwave uses the least electricity, although it has a lower cooking power. It is perfect for a small family or even a single-person household, as well as for students. 
2. Standard microwave – uses 800-1,000 Wh – these are usually medium to large residential microwaves that are larger than compact microwaves. They are perfect for a family of four or more and have a higher cooking power and electricity usage. A modern microwave is generally a standard microwave. 
3. Commercial microwave – uses more than 1,000 Wh – this type of microwave oven has a high energy consumption but also the lowest cooking time. They are used in restaurants and hospitals and allow for a large amount of food to be heated in a short time. However, they use a lot of power – generally more than 1 kWh for every hour they run. 

Importance of Watts in a Microwave

As we’ve said earlier, every microwave oven has a different wattage. But how important is this wattage, and what is the difference between a 600 Watt model and a 1,000 Watt microwave? Well, each side of the spectrum has its pros and cons. Let’s compare them: 

• 600-800 Watt microwave oven – this type of microwave oven capacity wattage is very low. This means it takes more than an hour of continuous work to use at least a kilowatt-hour of power. If you want to save electricity and lower your electricity bill, this is the right choice. However, the power level and performance when cooking food are very low, and it takes a longer time than with a more powerful microwave. 
• 800-1,000 Watt microwave over – this type of microwave uses more electricity than the compact microwave. However, you can cook food quickly as the power levels are higher. This microwave runs on more energy, but it does everything faster – from heating to cooking, you are sure to save time. 
• 1,000+ Watt microwave – This type of microwave has a higher wattage and power consumption but is also sure to cook microwave dinners in minutes. Almost like a conventional oven, it has a high power output and allows for power settings to be put into place. This way, you can save electricity when you do not need full power. Occasionally when you do, such as when you crave that ramen noodle right now, you will also have the comfort of getting the food quickly. 

To summarize, a lower wattage means lower power consumption and a lower price. However, it also means that you are limited with time, as these countertop ovens take more time to do the same work as a large, good microwave. On the other hand, large models have higher power consumption but can do the same work in a shorter time. When choosing your next microwave, pay attention to the microwave’s wattage and know that an average home microwave oven has a wattage of 800-1,000 Watts. 

Searching for the Wattage in a Microwave

There are several ways to find your microwave wattage. You can usually find how much energy your microwave uses by checking on its backside – all electrical appliances have a label that says how many watts or kilowatts the device uses. This is the simplest way to do it. However, if you have a built-in model and cannot access the wattage data, there are two more ways to find out how much power it uses. 

Firstly, you can check your manufacturer’s website. You can do this with any new microwave, as the producers always keep the technical specification list on their website. Secondly, you can simply Google the model and find the technical details on the seller’s website. If you have no luck, you can compare the volume of your microwave with the power consumption: 

• Most 20 liter ovens use 800-850 Watts, 
• Most 23 liter ovens use 1,100-1,200 watts of power, 
• Most 28 liter models use 2,500+ Watts. 

Input Microwave Wattage

When checking your microwave wattage, on some models, you may notice two types of wattage: the input and the output wattage. The input wattage refers to the total power consumption of your microwave oven: the energy used for the display, the button panel as well as the energy used to cook food. This is how much electricity your microwave oven pulls from the wall socket. 

Output Microwave Wattage

Your microwave runs a small magnetron to produce microwaves. It is these waves that cook or heat food from inside out. You cannot find microwaves that use some other technology. The output microwave wattage is how much power this magnetron uses. Thanks to the advances in technology, higher wattage displays do not exist anymore, so the little energy used by the display, the button panel, and the beeper is very low. This means that the input and output wattage is very close. 

Microwave Efficiency (Input & Output Wattage)

Of course, no appliance is 100% efficient. The power efficiency of microwaves is lower than 100%, so normally, the rated power of your microwave, even in the eco mode, is going to be higher than the energy delivered to the food you’re trying to heat. This increases the cooking time and the total cost of food preparation, as even small foods need more energy than rated. 

In general, the efficiency of a microwave is around 65%. This means that a 1,000-watt microwave will only be able to deliver around 650 watts of heat in the form of microwaves to your food. Likewise, a 600-watt microwave will only be able to deliver 380 watts to the food, leaving some cold spots, especially with older appliances. 

For this reason, you should be looking for energy-efficient microwaves. Over the range, microwaves often do not meet this criterion, especially since the manufacturers have to pay more attention to safety. If you would like to get the most results per kilowatt-hour of energy used, look for 80%+ efficiency models with eco mode and a high rated power. This way, you save energy, money, and time. 

Calculating the Electric Consumption of a Microwave

Of course, understanding the wattage of your microwave is just a part of the issue. Understanding how much power it actually consumes is a whole different problem. To understand this, you will need to know the exact wattage (the input wattage), as well as the daily usage. This will tell you the exact kilowatt-hours that your microwave uses and will also let you know how much of your electricity bill goes for the microwave. 

Let’s say that you have a 1,000 Watt microwave. Your family has four members, and each member uses the microwave for 10 minutes a day. Moreover, you use the microwave for 25 minutes in the evening to cook microwave dinners for the entire family. Let’s calculate how much energy your microwave uses. 

First things first, we need to see how long the microwave si used every day. To do this, we will sum all the usage throughout the day, so: 

4 members X 10 minutes + 25 minutes in the evening = 65 minutes

Then, we will multiply this number by the 1,000 watts per hour that the microwave uses. Since the microwave works for 65 minutes, we conclude this is 1 hour + 1/12 (5 minutes) of an hour. So the microwave uses a total of: 

Time Used X Input Wattage = Total Energy Use (how much energy your microwave uses in an average day) 

1 hr 5 minutes X 1,000 Watts = 1,083 watts 

Now we divide this number by a 1,000 to get kW: 

1,083 / 1,000 = 1.083 kWh 

Microwave on Standby

However, the power consumption does not end here. Every appliance and device you have has a small power consumption when in standby mode. This mode allows microwave use to be almost instant but draws some power even when the microwave is not in use. Although low, this still results in some electricity being used by your appliance, and it comes at a certain cost. Almost every appliance draws between 1 and 5 watts on standby mode, and your microwave is not an exception here. 

Let’s calculate how much electricity your microwave uses on standby mode in a year. We will take the average of 5 watts your microwave draws every hour. Although a small amount, it soon adds up to a kWh or even more. Let’s multiply this use by 24 hours a day and 365 days a year: 

5 Watts X 24 Hours X 365 Days = 43,800 Watts a Year! 

43,800 Watts / 1,000 = 43,8 kWh per Year

At an average cost of $0.1372 per kWh of electricity in the US (the national average for 2021), this means that the cost of leaving your microwave plugged in is equal to: 

43,8 kWh X $0.1372 = $6.006 per year 

This may not seem like much, but multiply this number by the number of appliances you have sitting on standby. Some computers use 8 Wh when plugged in, and the same goes for every device that has a status diode (LED diode), a display, or a charger of one kind or another. Add all of these up, and you are looking at $50-100 per year in potential electricity savings. 

The Cost of Using a Microwave

Now we know that most of the time, microwaves sit and occupy counter space without being used. There is no specific microwave that uses no power when on standby, so the true cost of running microwave for a year may surprise you. We will get this cost by adding up the standby usage, and the kilowatt-hours used when the microwave is running and then multiplying this number by $0.1372 per kilowatt-hour. Let’s dive in: 

Standby Use: $6.006 per year

Effective Use: 1.083 kWh X $0.1372 = $0.1485 per day or 

$4.4576 per month or 

$54.2341 per year

Standby Use + Effective Use = Total annual cost of running a microwave

$6.006 + $54.2341 = $60.2401 

The Top Energy Efficient Microwaves

There are too many microwave models out there to name, so we did a bit of research, and we’ve tried to find the best energy-efficient microwaves on the market. These microwaves use less power to both cook your meal and to be on standby for you. Here are the top energy-efficient microwaves: 

1. Farberware Classic 0.7 Cu. Ft. 700-Watt Microwave Oven – at 700 watts, this model is perfect for a small family. 
2. Toshiba EM131A5C-BS Microwave Oven with Smart Sensor & ECO Mode – ECO mode reduces standby power consumption by up to 50%, 
3. Panasonic Microwave Oven NN-SN686S Stainless Steel with Inverter Technology & Genius Sensor – with Inverter Technology, this microwave is sure to use less energy every time you run it! 

FAQs

Conclusion

Microwaves are a great device that can be found in any American household. With an affordable price and many uses, these appliances have found their way into the American household and the heart of many Americans, but they do come at the cost of running, reparation, and replacing. To best understand how much power they use and at what cost for you, use our guide to understand how many watts a microwave uses. 

Updated on 01-23-23