How Much Electricity Does an Air Purifier Use?

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We all desire clean, healthy indoor air quality, so it’s no surprise that air purifiers have become a staple in many households. But if you’re someone who is still on the hunt for one, one of the things you’ll want to know is how much energy these devices consume.

In general, air purifiers are designed to be energy efficient. However, the amount of electricity these energy-efficient air purifiers use depends on a range of factors like their wattage, size, type of filter it uses, operating speed, and how often you use it.

Below, we’ll teach you how to calculate a purifier’s power consumption and the cost of running one in your home. We’ll also go over the different factors that may affect how much energy they use.

Factors Affecting an Air Purifier’s Energy Consumption

Factors Affecting an Air Purifier’s Energy Consumption

Before we get into the cost of running an air purifier in your home, let’s talk about the different factors that affect its energy consumption.


The power rating or wattage of your unit, along with the average electricity rate in your area, is the main indicator of the amount of energy it consumes. Higher wattage typically means higher energy consumption. This also means higher operating costs.

Type of Filter

Air purifiers come in different types of filters. And each has different energy requirements.

High-efficiency particulate air (HEPA) filters are the minimum standard for all air purifiers. This type of filter is generally more efficient than carbon filters as it can trap smaller particles with higher efficiency. Because of this, the air purifier does not have to operate as long to purify the air.

Carbon filters, on the other hand, often consume more energy to run due to the longer dwell time required to capture pollutants and odors. Plus, they almost always need to be larger units to efficiently adsorb the same amount of pollutants.


If you have a large room, you’ll need a larger air purifier. And large units require large components like fans and filters, which also means higher watts and energy consumption. Below are some rough estimations of how varying sizes of air purifiers influence your energy use.

An air purifier that uses 100 watts of power, for example, consumes around 0.8 kilowatt-hours (kWh) every hour of use if you run it for 8 hours. For mid-sized air purifiers with 50 watts of power, the power consumption would be 0.04 kWh.

Smaller units are the least expensive to operate. Running a small air purifier with a power rating of 24 watts for an hour will consume 0.192 kWh.


The maximum coverage of air purifiers can range from small room-sized units to large ones. Large units usually offer an area of coverage ranging from 100 to 500 square feet or more. They are efficient at cleaning the air in large spaces, especially commercial-grade ones.

That said, they also require a more powerful air filter to cover a large room. This means they have to run at a faster speed, which can result in higher energy consumption.

Air Purifier’s CADR

An air purifier’s CADR (clean air delivery rate) is the amount of filtered air it delivers, which is expressed in cubic feet per minute (CFM).

It doesn’t directly affect its power consumption, but it’s an important factor to consider because the CADR per watt rate of the unit helps you determine whether or not an air purifier is energy efficient. In that, the higher the CADR per watt rate in your air purifier, the more energy efficient it is.

Air purifiers remove smoke, dust, and pollen from the air. These are the three particle sizes, with smoke being the smallest and pollen being the largest. So, the CADR per watt rate for each particle varies.

Air Purifier CFM

The CFM of an air purifier is the amount of air it can circulate and clean in a minute, which is reflected in its CADR. It doesn’t tell you how energy efficient your air purifier is. But, it can help you determine the amount of air it can move in space. And, just like its CADR, varies depending on the particle it’s removing.

A higher CFM indicates a faster air cleaning rate, however, it usually requires more energy to work. When it comes to this factor, the balance between its CFM and power consumption can tell you how energy efficient it is.

A well-designed unit with a lower CFM rate may be more energy efficient than one with a high CFM, but only if it eliminates pollutants effectively while consuming less power.

Overall, while a high cubic foot per minute may enhance the speed at which the air purifier cleans the air, it doesn’t always mean that it’s more energy efficient.

Technologies Used

Is your air purifier equipped with an ultraviolet light or ozone generator?

Such features are found in many models to further clean and sanitize the air that passes through the unit and its internal components. Now, these are great features, but they come with a cost. You may expect an increase in your electricity bill depending on how long they’ve been used.

Running Speed

Air purifiers come with various fan speeds: low, medium, and high. They are usually designed to let you choose between two fan speed settings. If you opt for low-speed mode, the device won’t provide much air purification and will consume the least amount of energy.

If you set it to the highest speed, it may give your room a more effective air purification while still being energy efficient.

So, How Much Electricity Does an Air Purifier Use?

How Much Electricity Does an Air Purifier Use

According to the U.S. Energy Information Administration (EIA), the current average price of electricity in residential homes is 16.09 cents/kWh. Using that metric, here’s a sample estimation of power consumption and cost for different wattage of air purifiers:

WattageHoursEnergy Consumption (kilowatt/hour)Daily CostMonthly Cost
24 watts80.192 kWh$0.031$0.96
50 watts80.4 kWh$0.064$1.98
75 watts80.6 kWh$0.097$3.01
100 watts80.8 kWh$0.13$4.03

These examples are based on an 8-hour use period. To calculate how much electricity your air purifier consumes based on your average hour of use, follow this formula:

100 (wattage) x 8 (hours) = 800 / 1000 = 0.8 kWh

To get the average hourly cost:

0.8 kWh (energy consumption) x 0.1609 cents/kWh (average electricity rate) = $0.031


Do Air Purifiers Increase Electric Bill?

It depends on how long and often you use it. An energy-efficient air purifier consumes relatively low amounts of electricity. Plus, they are worth the investment, especially if you live in a highly-polluted area. That said, if you use it for an extended period of time, these units can use a lot of energy.

How Much Does It Cost To Run an Air Purifier 24 Hours a Day?

It depends on the size, running speed, features, and average electricity rate in your area. If you run a 100-watt air purifier for 24 hours, based on an average rate of 16.09 cents/kWh, it may cost you $0.37 a day. Refer to the formula above to calculate your daily air purifier power consumption.

Should I Run Air Purifier on All the Time?

It depends on several factors. Consider the air quality in your environment, the size of your room, and any health concerns you may have. Running your room air purifier allows you to keep air quality in a room or home at a comfortable and healthy level.

Can I Leave My Air Purifier on All Day?

You can. In high-pollution environments or for individuals with respiratory issues, running the purifier continuously is usually the best. But it’s recommended that you run an air purifier for at least 8 hours a day in a medium-sized room.

It’s also fine to not follow such patterns every day. But keep in mind that the more you operate your air purifier, the fresher and cleaner the air will be.


Considering how much electricity air purifiers use and how much it costs to run one can help you decide whether it’s right for your budget. Thankfully, they usually have high energy efficiency rating, but you still need to manage your daily usage.

We hope you found this information helpful and let us know if you have more questions. Good luck!