How To Cook Frozen Mozzarella Sticks In An Air Fryer – An Easy, Cheesy How-To Guide

Featured image for how to cook frozen mozzarella sticks in an air fryer

What comes to mind you hear the words “mozzarella sticks”? Is it soft, bland, reheated cheese sticks or delicious, fresh and hot cheese you can’t get enough of?

hate poorly cooked cheese sticks to I did the hard work to find out the best way to cook them…and to help you do the same!

In this simple guide, you’ll learn how to cook frozen mozzarella sticks in an air fryer with excellent results.

It’s fast, easy, and you’ll love how they taste. Let’s go!


Infographic – How to cook great frozen mozzarella sticks

How to cook frozen mozzarella sticks in an air fryer infographic guide

Quick summary: Cooking frozen mozzarella sticks in an air fryer

Cooking frozen mozzarella cheese sticks at home is very easy. However, it’s helpful to know some things ahead of time to avoid headaches or messing up your food.

Basic steps for cooking frozen mozzarella cheese sticks in an air fryer
  1. Preheat the air fryer – Typically you’ll just need to let the air fryer run at the cooking temperature (350°F is recommended) for 5 minutes
  2. Place the frozen sticks in the fryer basket – For best results, shake the container to even them out inside. For a slightly crispier outside, use a cooking spray to lightly coat them. Canola oil is a good choice.
  3. Cooking: With the temperature set properly (350°F is good), cook for 4-5 minutes. After 2 minutes, shake the sticks to turn over uncooked areas for hot cooking air. Spray cooking oil again if desired. Start the air fryer again.
  4. Final cooking: Your cheese sticks should be ready to eat after 4 minutes. For a bit more crispiness, you can cook to 5 minutes time (note that cheese may leak in some cases). Don’t overcook the sticks.
  5. Empty the cheese sticks using a fork or tongs and serve. For best taste, serve immediately before the cheese can cool and the outsides soften. Add a dipping sauce like marinara and enjoy!

How & why to preheat your air fryer

Image showing preheat settings for air fryers when cooking cheese sticks

Top: Preheating an air fryer with digital controls. These often have a preheat mode button (some may use less than 5 minutes and adjust their time automatically). Bottom: For standard models, you can preheat the fryer by adjusting it to the 350° temperature and setting the cooking timer for 5 minutes.

Just like with regular ovens, air fryer makers recommend warming up the fryer to the cooking temperature before you add food. But why is that?

You should preheat your air fryer for several reasons:

  • The electric heating element gets heated and ready to use
  • Inside surfaces that touch & cook food are hot and ready to work properly
  • Preheating avoids a warming delay that would happen if you started cooking from room temperature

In other words, you’ll get your air fryer ready to begin cooking right away – it’s preheated (already heated) and ready to use. You won’t have to worry about trying to adjust cooking time for a cold fryer.

As some people warm up their car during the winter cold before driving it, the idea is the same.

Preheating means proper cooking

For food that’s heated properly and cooks well you’ll need to let your air fryer warm up. Doing this allows your meals to cook consistently and reliably.

It’s true that air fryers are small and don’t take as long as larger traditional ovens do. However, they still need a few minutes before they’re ready.

How to preheat your air fryer

Image showing temperature measurement of Dash air fryer preheat time

I recorded preheating times needed to get my air fryers ready before cooking frozen cheese sticks. I found out that they actually reach the cooking temperature before 5 minutes. However, the air fryer self needs the extra time (4-5 minutes total) to get completely ready. The internal surfaces will be hot and ready to cook the food as soon as it touches it.

Preheating is really easy! However, the way you go about doing it depends on the type & model of air fryer you own.

One of two ways are used:

  • Digital controls/push button models: These often have a preheat button. When used, the unit will heat itself for the time required then shutoff. You can also set the temperature and cooking time manually to do the same thing. (Note: Some models may use a bit less time to preheat with automatic settings, which is fine)
  • Air fryers with dial controls can be set to the cooking temperature then set for 5 mins cooking time. When the timer is done you’re ready to add food and start the cooking process.

In either case, 5 minutes is a preheat time to use. For the preheating temperature, set it to 350°F as we’ll use that for cooking.

Getting your mozzarella sticks ready to cook

Image showing how to prepare frozen mozzarella sticks in air fryers for cooking

It’s easy to get your mozzarella cheese sticks ready for cooking in your air fryer. For the best results, fill the fryer basket with the frozen sticks then shake them to help even them out. This helps them get the best exposure to hot cooking air. As cheese sticks can be a bit soft on the outside when done, to help them cook better and for more crunchiness spray them with good cooking oil like canola oil. 

Yes, it really is easy to cook cheese sticks, but I want you to get the tastiest, well-cooked cheesy goodness possible. Here’s how to get your frozen cheese sticks ready for the best cooking possible:

  1. Add the frozen sticks to the fryer basket. If you’ve got a really big bag of them, be sure you don’t pile them above the top edge of the container.
  2. Shake the basket container until the pieces “even out.” That is, shake them until they spread out a bit inside. This helps them cook better as they get more even exposure to the hot air that cooks them (This is really important if you’re cooking a lot of food in an air fryer)
  3. Since frozen cheese sticks may be a bit soft after cooking, you can help them crisp better by using a light cooking oil before you start the timer. Spray them lightly until they look slightly wet. Canola oil cooking spray is a great choice.
  4. Place the fryer basket back inside the air fryer.

When cooking with an air fryer what you don’t want to do is to let your mozzarella sticks pile up inside. It’s important that they get exposure to the cooking air inside.

Food that’s stacked on top of each other (like when you’re cooking a large bag full of cheese sticks) won’t cook as well.

That’s one reason I recommend shaking them a bit.

Using a cooking spray

Image showing an example can of canola oil cooking spray for air fryer use

One great tip is to use a cooking spray like canola oil or olive oil to lightly coat your food before cooking. Doing so helps your food crisp better and get a wonderfully crunchy outside.

The same is true not only for cheese sticks but also chicken wings, tater tots, french fries, and many other great foods you’ll want to cook in your air fryer. It’s a tip I picked up from my Cuisinart air fryer & toaster oven owner’s manual.

To use cooking spray with an air fryer, put the food inside then lightly coat the top of the food until it looks slightly wet. You won’t need much – just enough to coat the outer surface.

How long should I cook frozen mozzarella sticks?

I measured cooking times for frozen mozzarella cheese sticks until they were well-done and tasted good. Both the larger air fryer (a 3.7 quart Cosori unit) and the smaller one, a 1.2 qt Dash personal air fryer, only needed 4 minutes In both cases I shook the contents after 2 minutes and re-sprayed the canola oil.

To better test the size & power levels of air fryers that many people will use, I made tested cooking times using 2 sizes & power ratings: A Cosori 3.7 quart 1700W model (great for families) and a smaller personal air fryer, the Dash 1.2 quart 1000W model.

What’s I found is very interesting: Unlike other foods like fries, wings, or chicken nuggets, cheese sticks cook VERY quickly!

Here’s a brief timeline of what happens when cooking frozen cheese sticks:

  • 0-1 mins: Thawing, starting to warm up
  • 1-2 mins: Inside is no longer frozen or cold
  • 2 mins: Need to shake the sticks & move around for good cooking heat exposure
  • 3-4 mins: Outside is warming & crisping, inside cheese is heavily melted and hot
  • 4 mins: Hot, fresh, and ready to eat!

Your cheese sticks will be ready to enjoy after 4 minutes of cooking. I cooked them for 5 minutes for a bit more crisping on the outside.

While crunchy cheese sticks are wonderful, the downside is that a bit more cheese may leak out as it’s so hot.

Be sure you don’t cook past 5 minutes because the cheese will liquefy and drip into the bottom of the container.

Don’t forget to shake them!

Image showing example of shaking cheese sticks in an air fryer while cooking

After 2 mins it’s a good idea to shake your cheese sticks inside the fryer basket. This helps expose lesser cooked sides to the hot cooking air. Lightly spray cooking oil again then place them back into the air fryer.

For the best cheese sticks you can cook, remove them and shake after 2 minutes. This will turn them over and the sides that had less exposure to the air fryer’s hot cooking air will now get more.

If you’re using a cooking spray, coat them again now.

Put them back into the fryer and you’re done in 4 minutes total time (Your fryer’s cooking timer should be set to 4 minutes already anyway.

Your mozzarella sticks should now be fresh, hot, and fantastic!

Example of checking the internal temperature of cheese sticks while cooking with a digital thermometer

Tip: Keeping a digital food thermometer handy is a great idea. Using one, you can be sure frozen foods are cooked well by checking the internal temperature quickly (and cook longer if needed). For frozen foods like cheese sticks or burritos, an internal temperature of 100°F and higher is good. I use a ThermoPro TP03A digital kitchen gauge as it’s cheap and works well.

Final touches and we’re done. Let’s eat some cheese!

Image showing correctly cooked air fryer cheese sticks up close

Cheese sticks are easy to empty and put on your plate or another container after cooking (unlike foods such as wings and tater tots for example). Use a fork or a tong to make it a snap. The great news also is that cheese sticks don’t produce a lot of oil when cooking so there’s not much to clean up afterward. Note: A little bit of cheese leaking from the sticks is normal, so don’t fret if you see some.

Once you’re done cooking either pour them out directly or use a fork or tongs. (I recommend getting a cheap pair of tongs as they’re very handy for the many kinds of air fryer foods you’ll want to make)

The great news is that there’s not much to clean up afterward in most cases as cheese sticks don’t produce oil when the cook as some other foods do.

What to expect

You might find some leaked cheese at the bottom of your fryer basket (see further below for what I mean) or a tiny bit of crumbs and residue, but that’s about it.

Properly cooked cheese sticks will still be very hot right after cooking so don’t use your hands. They’ll cool off quickly, however, so don’t waste much time before serving them.

I strongly recommend serving your fresh cheese sticks right away. They cool off quickly and just won’t taste the same when that happens!

The sauce makes it even better!

Image showing marinara sauce example served on plate with cheese sticks

Pick up some marinara sauce as it makes a great dipping treat to eat with your fresh, hot mozzarella sticks you just made. It’s a traditional meal and I highly recommend it if you’ve never tried it.

Add some marinara dipping sauce and now you’ve got a hot, delicious, and cheesy snack or meal you’ll love!

Note: I don’t recommend using a microwave oven to reheat your sticks once they’re cold. It’s just not the same and won’t taste nearly as good.

For best results, warm & crisp them back to a tasty & fresh state by reheating them in a hot air fryer at 350°F for about 1-2 minutes.

The delicious results

Image showing properly served cheese sticks served on display

Yay! It’s time to eat. Get ’em while they’re hot! Serve up your cheesy goodness with your favorite dipping sauce or sides. For a classic cheese stick meal, I recommend traditional marinara as it’s a great match.

You’re done and it’s time to eat! It’s amazing how fast, easy, and healthy cooking them yourself in an air fryer is.

In fact, I find that because they’re not cooked in dirty cooking grease like at a restaurant, they taste much better! There’s nothing between you and that REAL mozzarella cheese flavor – and no grease soaked into them or dripping to make a mess, either.

Clean up & last notes

Image of dirty air fryer baskets after cooking frozen cheese sticks

Things MIGHT get a little bit messy after cooking cheese sticks. Cheese sticks might leak a bit of cheese, so be aware there might be a LITTLE bit to clean up afterward. However, it’s actually very easy to clean so don’t worry!

What I discovered during cooking testing different foods in air fryers is that many foods (especially meats) like chicken wings tend to leave behind a fair amount of grease & fat after cooking

What’s especially great about mozzarella cheese sticks is that they don’t. While you’ll find a few crumbs and leaked cheese you’ll need to clean up afterward, it’s not bad.

To keep the leaked cheese to a minimum don’t cook them past 4 minutes. After 4 minutes I saw much more cheese leaking out of the sticks into the bottom of the basket.

Either way, clean up is really easy only take a minute or two.

Image showing example washing an air fryer cooking basket in the sink

Washing out the fryer basket is really easy. Cleaning out leftover cheese is no problem at all.

Just add a drop of dishwashing detergent after filling it with warm water. Any leftover cheese will soften quickly and will be easy to wash out.

Gently wash the inside with a sponge or soft cloth because you don’t want to damage the nonstick coating inside. Washing a basket and its parts out usually only takes 60 seconds or less once the water is hot.

Let the parts air dry or use a towel if you like afterward. (Note: Most air fryer baskets are dishwasher safe so after cleaning out the drippings you can put them in the dishwasher)

More air fryer cooking guides

Want even more delicious food you can cook in minutes? Check out my other guides based on hands-on testing, measurements, and most of all….taste!

Are Air Purifiers Good For Your Health?

Image of child in living room with air purifier

Your home is your safe haven and should be a place that feels great to come home to. But did you know it can harbor some harmful gases and pollutants?

According to the Environmental Protection Agency (EPA), indoor air contains organic chemical pollutants at levels 2 to 5 times higher than those found in outdoor air. Knowing that maybe it’s time to invest in a good air purifier.

But wait – are air purifiers good for your health? Or could they be potentially harmful as well? And which ones are the right kinds to buy?


Answering the basic question – Are air purifiers good for your health?

First off, before going into more detail, here’s a quick answer to your question:

Ultimately, it comes down to this: Yes, the right type of air purifier is good for your health. The wrong type can cause health issues or discomfort.

  • HEPA filter-based air purifiers produce no harmful by-products and are good for your health. They remove harmful and allergy-causing particulates from the air, leaving only fresh air behind.
  • Ozone generators are a poor choice and are potentially harmful. Additionally, they’re very ineffective for air cleaning when compared to HEPA type air purifiers.
  • Ionizers are generally a good way to effectively combat airborne germs that cause illnesses. However, like others, they’re not efficient or effective for the most common air quality problems. Again, a filter-type based purifier is a much better choice.

I’d like to explain exactly why this is – and what kind of purifier you should – or should not – buy.

Some are simply junk and a waste of money. In fact, some can make you cough, feel poorly, and are not good for your health!

Common home air quality problems

(Click image to enlarge)

Indoor pollution is best dealt with by eliminating the pollutants and ventilating your home. Some of us can open windows and let fresh air in for a while, but the problem is that’s a temporary solution – it won’t fix the source of the problem.

While there are too many to list here, some of the most common problems are:

  • Allergens from plants and other materials
  • Pet odors, hair, and pet dander
  • Bad smells from a variety of sources
  • Sneezing, coughing, and sniffling
  • Irritants causing red eyes or scratchy skin
  • Dust mite problems
  • Stale air that doesn’t smell fresh
  • Dust
  • Volatile organic compound (VOC) substances from chemicals

Image note about pet allergies

Unlike temporary solutions, an air purifier can remove air contaminants, pet dander, dust mite irritants, dust, smoke odors, and much more. Some of the most common problems we all suffer from can improve a lot!

Ultimately, the only way to truly deal with an air quality problem is to get rid of the source! If that’s not possible (for example, getting rid of your pets) the solution is to remove the cause as it’s produced.

To do so, however, you’ll want the right kind of product that won’t expose you to potential health symptoms. You’ll also want something that’s effective, too. Otherwise, what’s the point?

Air quality problems air purifiers can help with

Dirty air purifier filter that has collected dust

Shown: My air purifier’s filter after being used only about 2 weeks and capturing LOTS of dust. I was amazed at how much it removed from my room and the air around me!

There are two kinds of indoor pollutants commonly found in homes:

1. Particulate matter: Pollen, dust, debris, hair, pet dander, smoke, molds, bacteria, viruses, and other tiny organisms. Newer homes may contain airborne particles related to new carpet or building materials indoors.

Sometimes matter is brought in from outdoors. A great example is smokers who bring smoker particles inside your home on their clothes & hair, or dirt and plant particles from other places.

2. Gaseous pollutants: The usual household sources, including ingredients in fuels, medicine, perfume, cosmetics, plastics, and other products used for things like cleaning, cooking, or maintenance. Others include smoke or pet odors also.

How does an air purifier work?

How air purifiers reduce dust diagramAn air purifier works by drawing in dirty, contaminated air which is then filtered before it escapes back into the room. A great example is the popular GermGuardian AC4825. An activated carbon filter traps gaseous substances (and larger particles, as it acts as a pre-filter). This particular model also includes a germ-killing feature using ultraviolet (UV) light.

An air purifier is an electromechanical device that cleans indoor air either by removing or destroying the pollutants. Most use a fan to pull dirty air from an enclosed space (your bedroom, kitchen, or living room, for instance) and force the air through a filter or series of filters, trapping unwanted contaminants.

The clean air is then released back into the room. This continues and is a process of continuously cycling air over and over until the room is purified.

Since each group of pollutants has different characteristics, the air purifying system that will work for each of them will also differ.

Some systems work by removing pollutants by one of 3 ways:

  • Mechanical filtration – applicable for particulate matter
  • Electrostatic attraction – applicable for particulate matter
  • Gas absorption – applicable for some gas pollutants

Other systems work by destroying pollutants and work as follows:

  • Ultraviolet (UV) light radiation – applicable for molds, viruses, bacteria, and other biological pollutants
  • Photocatalytic oxidation (PCO) – also uses ultraviolet lamps and is intended for gaseous pollutants
  • Ozone generation – produces ozone molecules (O3) from surrounding oxygen to trap particulates, gases, and biological pollutants

The different types of air purifiers

There’s a number of different types of air purifiers that you should know about, although not all are found in consumer products. Just the same, it’s very helpful to have an overall awareness of what’s out there.

Several of these aren’t something you’ll find when shopping for a product for your home, so don’t stress out about it.

1. HEPA filter purifiers

A HEPA filter is an extremely dense filter made up of many extremely dense fibers packed together. The material traps microscopic particles in the air passing through it. They’re highly effective at cleaning the air and don’t have any undesirable side effects unlike other methods used. Often a HEPA filter is used along with a pre-filter and an activated carbon filter.

The most commonly available type in the consumer market, these are air purifiers that capture particulates using filters. High-Efficiency Particulate Air (HEPA) filters fall under this category and are the standard type you’ll find when shopping.

A HEPA air filter is made of very thin glass fibers randomly woven into a mesh material which is folded to increase its surface area.

Extremely dense in construction, they’re capable of capturing and removing 99.97% of particulate matter as small as 0.3 microns in size (a micron is 1/1,000,000 of a meter).

While there are other types of filters used in some cases (such as HEPA “type”), they’re not as effective if they don’t meet the government specifications the HEPA filter standard requires.

Normally they’re used along with 1 or 2 more filter sections such as a mesh prefilter (for trapping dust, hair, and larger elements) and an odor and gas-absorbing section.

2. Electronic air cleaners

Orion B-1000 air purifier with filter shown

Electronic air cleaners like this B-1000 ionizer shown here work by generating charged particles. These particles then can cling to particulates in the air as well as neutralize germs, too. A well-designed unit collects the foreign matter in a filter (shown) or on a plate.

Electronic air cleaners draw air into an ionization section where particulates are electrically charged.

Electrostatic air precipitators and air ionizers are two examples of electronic air cleaners. In the case of precipitators, these charged particles are attracted to plates with an opposite electrical charge as they pass through in the air, removing them from the air.

Ionizers create the charged particles which bond to air particles and then metal collection plates or a filter inside the device.

Unlike air filters that are tested using HEPA standards, there’s no way to gauge the effectiveness of electronic air cleaners. They also produce small amounts of ozone – a three-oxygen molecule which can irritate the lungs – as a by-product.

Why ionizers are a bad choice

Ionizers have been proven to rid the air effectively of sickness-causing microbes, so they can offer a great benefit if designed correctly.

Despite this, they can’t purify the air nearly as effectively as filter-based purifiers can. If you’re considering buying an ionizer purifier, it’s important to be aware that most aren’t really worth the money.

3. Ozone generators

Image of ozone generatorOzone generators produce heavy amounts of ozone molecules by using a high voltage device to split oxygen molecules. The oxygen atoms recombine as ozone (03). These can bond to particles in the air and may give the impression of fresh air being generated. They don’t permanently trap particulates in the air as filter-based types do.

Ozone generators are a type of air cleaner designed to oxidize biological contaminants, odors, gaseous pollutants, allergens, and particulates. Ozone has to be used in high concentrations to be effective.

At first glance, it can seem like ozone is a great way to eliminate pollutants in the air without even needing a filter or even fans in some cases. Many sold today on the market are listed with big claims and fancy technical terms but in truth are very poor performers.

Unfortunately, ozone can exacerbate symptoms in asthma sufferers, cause shortness of breath and throat irritation, and even lower the body’s ability to ward off respiratory infections.

In fact, the EPA recognizes ozone as a lung irritant and products often have ratings to let you know how much they produce.

Sales gimmicks and your money

As I mentioned earlier, ozone generators are often sold with misleading advertisements to make consumers think they’re effective and will freshen the air well. The truth is, they really don’t!

Ozone itself can attach to airborne particles and trap it, but the problem is that it takes an excessive amount of ozone for them to be anywhere near effective. Therefore, they aren’t recommended for enclosed rooms and especially not for people with asthma or other respiratory problems.

Diagram showing ozone production and pair particles
Some air purifiers have an ionizer or ozone generator as an extra option. These types are less likely to produce unsafe levels as they’re a secondary feature and aren’t a health threat in most cases.

The most prevalent problem with ozone generators is that they can’t purify the air efficiently as a filter-based product can.

4. Ultraviolet (UV) germicidal irradiation air cleaners

Diagram showing how UV light kills germs & DNA

Ultraviolet light damages the DNA of airborne germs and microbes at the molecular level, rendering them harmless.

UV-based cleaners are intended for the destruction of molds, viruses, and bacteria either airborne or populating along the HVAC ductwork. These serve primarily to cleanse the air of germs and don’t remove particles and other foreign matter from the air as filters do.

However, many of these biological pollutants produce higher levels of UV radiation than is provided by most UVGI cleaners designed for home use. Dead or inactivate microorganisms can still trigger allergies and respiratory problems.

Also, there’s no way to tell how effective UV cleaners are since there aren’t any standards to test them or compare them when buying.

In air purifiers available for home use, the UV feature serves as a side benefit for reducing airborne germs and microbes.

In summary – Are air purifiers good for your health?

Ultimately, it comes down to this: Yes, the right type of air purifier is good for your health. The wrong type can cause health issues.

  • Filter-based air purifiers produce no by-harmful by-products and are good for your health. They remove harmful and allergy-causing particulates from the air, leaving only fresh air behind.
  • Ozone generators are a poor choice and are potentially harmful. Additionally, they’re not nearly as effective as filter-based products.
  • Ionizers are generally a good way to effectively combat airborne germs that cause illnesses. However, like others, they’re not good for efficient and thorough air cleaning. Again, a filter-type based purifier beats them in that area.

Ideally, for the best health buy a true HEPA filter-based purifier. These will reduce airborne allergens and particulates that cause problems. A model with an ionizer or UV germ-killing feature is an ideal choice and won’t cause health issues.

These won’t produce excessive amounts of ozone and the UV light won’t be a health hazard for your either.

It’s very important to buy a reputable, proven brand that isn’t misleading you with hype or false claims. Many sold (especially from China) are simply ozone generators that are bad for you and simply don’t work well!

Don’t worry, though! You can buy a great HEPA filter purifier for under $100. You can find some great choices you can afford in my detailed post here.

Ionic Air Purifiers Vs. HEPA Purifiers – What’s The Difference?

Ionic air purifier vs HEPA featured image

Are you trying to understand the difference between an ionic air purifier vs. a HEPA purifier? I’ll be honest and admit a long time ago I was confused too. One reason is because of misleading product descriptions I had to research and verify.

It seems like there are so many products sold today as air purifiers. And many are falsely described – which makes it even more confusing! My main goal is to answer your questions about both the differences between an ionizer purifier vs. HEPA purifier.

Before spending any money it’s well worth taking a few minutes to find out more what you really need. I want you to get the best for your money and the best product for your needs.


Infographic – Ionic air purifier vs. HEPA

Ionic air purifier vs. HEPA infographic diagram/image

What does an ionic purifier do?

ionizer purifier examples

Examples of two popular and commonly sold ionic (ionizer) air purifiers. Left: O-ion B-1000 purifier and (right) the No products found. Both use charged plates to attract particles from the air which collect in a filter or on plates for later removal. Both also use a fan to move air through the ionizer section of the purifier. Both also have a UV-C light feature to kill germs.

Air ionizers work by processing air moved by a fan using electrically charged plates to charge air molecules. These ions – or charged air molecules – are attracted to plates or electrodes very much like how static electricity works.

How ionizers work

Ionic air purifier how it works diagramShown: one of many ionizer designs. In this example (of a design used by better ionizer air purifiers) air is moved by a fan through the first filter. Following this, particles in the air are charged (ionized) and then attracted to metal plates of an opposite charge where they’re captured. A final filter removes some more particles in the air. Note that not all ionizer air purifiers have filters.

Ionizers come in different designs. Not all work the same.

For example, better models have a fan to circulate air in a room and others don’t. In order to purify the air in a room, a product absolutely must actually move the air through it and process it to remove contaminants.

Generally speaking, however, ionic air purifiers use a fan to move air through a series of electrodes and plates. The first plates use an electrical charge to ionize (change the electrical charge of) the airborne particles.

The 2nd stage features other electrodes or plates which have an opposite charge. When the newly charged particles move close to them, they’re attracted to them and bond to them, removing them from the air.

It’s very much like static electricity. For example, think about how pieces of paper, hair, or styrofoam are attracted to your body and clothes when you build up a charge on your carpet.

These contaminants collect on plates or similar type of filter where they’re cleaned off later. Some models feature standard filters as well.

Sometimes ionizers are a feature built into HEPA type purifiers as an added benefit.

One major strength of an ionizer is its ability to destroy airborne illnesses by killing microbes in the air.

Ionizers vs ozone generators

Image of ozone generatorUnlike ionizers, ozone generators produce a lot of ozone molecules in the air and don’t internally collect contaminant particles. The idea is for ozone to bond with airborne particulates which then fall from the air. They’re not very effective at safe ozone levels and at levels where they are effective, the ozone is potentially harmful to humans.

It’s important to cover this topic as unfortunately ionizers are often confused with ozone generators. Companies selling ozone-generating “purifiers” often mislabel them and it simply adds to the confusion.

By nature, ionizers do generate a very small amount of ozone but don’t generally do so at an unsafe or harmful level.

Ozone generators are different from ionizers in that they primarily generate ozone (O3 molecules) by using a high-voltage corona effect to split oxygen molecules in the air which form with other oxygen atoms.

They usually use a fan to blow these molecules into the room, but a lot of them don’t contain internal filters for trapping contaminants. Instead, particles fall to the floor around it.

Why ozone generators are a poor choice

I recommend you avoid these and decide between an ionic purifier and a filter-based (HEPA) purifier. Ozone generators aren’t effective and even if not harmful can irritate your respiratory system.

They’re also a bad choice for people with health issues related to emphysema and other conditions.

What does a HEPA purifier do?

Image of Levoit LV-H132 air purifier in bedroom

Commonly sold HEPA filter air purifiers like the Levoit LV-H132 are placed in rooms where air quality issues are present. Some of the most common locations are bedrooms and living rooms. They circulate air using fans, moving the air through different filters that trap unwanted elements. You’ll need to replace the filters with new ones once they’re saturated with contaminants.

HEPA air purifiers are designed to circulate air in the room and remove contaminants, dust, allergens, and more by trapping them in filters. Unlike ionic purifiers, HEPA purifiers always use a fan – it’s not possible for a product to work without one. Also, they generally do not affect air molecules using any type of electrostatic charge as ionizers do.

(Note that there are some exceptions which I’ll cover later)

A High-Efficiency Particulate Air (HEPA) filter refers to a particular type of filter designed to meet certain efficiency and air purification quality levels. These filters are made of a very dense fiber-like material.

The HEPA name describes a standard that mandates a filter can remove airborne particles down to 0.3 microns in size. A micron, or micrometer, is 1/1,000,000 of a meter. The efficiency of this type of filter is 99.97%, meaning that for every 10,000 particles flowing into it only about 3 escape.

They’re very effective at cleaning air.

How HEPA purifiers work

How air purifiers reduce dust diagram

HEPA filter-based purifiers don’t produce anything in the air or cause any type of electrostatic charge, unlike ionizers. They work off of a simple principle: using a fan or fans to circulate the air in a room and move it through filters. These filters trap both larger and microscopic particles, odors, chemical vapors, and many common household irritants.

HEPA filter purifiers are pretty simple in principle although many variations with more features exist.

They all share a similar design: A fan (or fans) is used to draw in air and force it through filters that trap odors and contaminants to blow out fresh air. They continue to do so in a circulation pattern to clean the air in a home or room within several hours.

Unlike ionizers, they depend on the fast movement of air and a filter. While ionizers use an electrostatic charge to remove particulates in the air you breathe, these rely on mechanical means.

In other words, instead of “attracting” particles in the air, they block and trap them in filters.

Some add more features

It’s worth noting that some filter-based purifiers may include unique features like an ultraviolet light (UV) germ killing option. Some may even include an ionizer feature themselves! However they still heavily rely primarily on filters to work effectively.

For convenience, some also offer more advanced features like an air quality sensor or auto-off timer. Others today allow smartphone control features.

Filters used in HEPA purifiers

It’s actually rare that a modern air purifier like this has only a HEPA filter. Today, most products include some variation of a “3-in-1” design:

  1. Pre-filter section
  2. Activated carbon (charcoal) section
  3. HEPA filter

The pre-filter is normally attached to an activated carbon filter section. It’s a thin material that traps larger matter like hair and dust. The activated carbon filter is the section that absorbs vapors and odors.

Ionic air purifier vs HEPA purifier comparison

By now you should understand more about how ionic and HEPA purifiers work. You really shouldn’t spend money until considering the pros and cons of each.

In order to make it a bit simpler, I’ve put together a comparison table that highlights the differences between the two along with a few notes. (Some characteristics are often different on a brand & product basis and are not true in all cases).

Ionic vs HEPA comparison table

Air cleaning process Charges air particles which are collected on plates or filter. Fan moves air through the purifier. Cleans air by circulating air. Air is forced through HEPA/pre-/carbon filters, trapping particulates
Ozone production Very small (< 0.05ppm typical) None
Germ killing ability Low to good, depending on product None to fair (some products feature germ killing ability)
Air flow rate Low-fair (fan speed often not selectable) Good-high (adjustable fan speed)
Dust cleaning Poor Good
Cigarette smoke cleaning Fair-good (particles to 0.01uM in some cases) Good (limited to particle size to 0.3uM and above)
Odor reduction Poor/moderate Good (models with carbon filter)
Pet dander cleaning Fair-good Good
Pet hair cleaning Poor Good
Allergy relief Fair Good
Filter maintenance Clean plates/wash filter (reusable) Replace complete or separate filters, depending on model (ave. 6-8 months life)
Average cost $50-$65+ $50-$100+

Which one should you choose?

Confused man in suit
Ionic purifiers do have a distinct advantage over HEPA type purifiers: their ability to sanitize the air and greatly reduce airborne germs which cause illnesses. Filter-type purifiers don’t normally have this ability although some like GermGuardian products do have a feature that uses UV-C technology to do so.

Some ionizers like the O-Ion B-1000 in the image above also have this feature, too.

However, when comparing the pros and cons of each, I recommend a quality HEPA-type purifier. They offer a higher rate of airflow for better clean air delivery, they’re good for dust and hair problems, and models with a carbon filter can absorb odors and chemicals in the air.

Another reason is that ionizers are not held to the same standards of performance and demonstrated air cleaning that filter models are.

For example, the Clean Air Delivery Rate (CADR) is laboratory tested and proven testing. It’s a standardized way of demonstrating an air purifier’s cleaning effectiveness. You won’t see that on ionic air purifiers.

When are ionizers a good idea or helpful?

Ionizers are good for light-duty cleaning like needing to freshen a room as well as other less demanding applications.

For pet dander, allergies, bad smoke problems, and others HEPA purifiers are the way to go. Additionally, the faster fan speeds mean air cleaning is more rapid and you have more control over it.

The major downside of HEPA purifiers is needing to buy replacement filters, which on average is about 6-8 months depending on the model. (Note that in some cases carbon filter can be replaced separately, extending the use of the main HEPA filter section).

Hybrid models

Holmes HAP116Z-U

Some models use both filters and an ionizer to clean the air. Note that purification effectiveness can vary greatly, so it’s very important to always buy a proven, effective product.

To (unfortunately!) make things more complicated, there are some hybrid models on the market which feature both a filter and a built-in ionizer section as an extra feature.

Primarily, however, you should always shop for a purifier on the basis of proven performance, great reviews, and cleaning ability for your room size. Don’t let marketing tactics mislead you into spending money on something that’s less effective.

Summary – Ionic vs. HEPA air purifiers

In summary here’s what we’ve learned:

  • Ionic (ionizer) air purifiers work by moving air. Airborne particles are charged and attracted to plates where they collect on plates or a filter. Ionizers are more effective at sanitizing air.
  • High-Efficiency Air Particulate (HEPA) purifiers move air through filters to trap particles, odors, and more. They don’t introduce anything into the air itself.
  • Ozone generators may be misleadingly sold as “ionizers’ but aren’t a good use of money, and aren’t effective. Ozone can irritate internal tissues. At high levels, ozone molecules can become harmful.

Be sure to do your reading before spending money!

One of the best HEPA purifiers sold today is the GermGuardian AC4825. It’s an effective purifier with good performance – and I own one! You can read my detailed review here.

If you’d like to see a good ionizer that’s moderately priced, check out the O-Ion B-1000 here as well.