Complete List Furnace Filter Made in USA by Sizes with Actual Size and MERV ratings available in 2024

Huge Discounts on Filter Sizes For AC and Furnace HVAC Filters for all Home Air Filter Sizes

  Atomic has the Experienced checked furnace filters in the Size Chart for all Furnace filters brands so you can trust you will find the correct OEM filter or save money on a compatible filter. Need Filter Help? Call 910-401-3910 M-F 10am-5pm Eastern. Find Your Filter and Save. It is that easy.

Furnace Filter Made in USA by Size by Model Number and Brand(With Nominal Sizes and Actual Sizes)

  Atomic Filters is a Proud Supporter of Folds of Honor

What are the Most Popular HVAC Filter Sizes? 

Most Popular 1 inch Air Filters made in the USA ( Experience Checked)

• 14x30x1 Air Filters BUY NOW
• 16x20x1 Air Filters BUY NOW
• 16x25x1 Air Filters BUY NOW
• 20x20x1 Air Filters BUY NOW
• 20x25x1 Air Filters BUY NOW

Most Popular 4 inch Air Filters

• 16x25x4 Air Filters BUY NOW
• 20x20x4 Air Filters BUY NOW
• 20x25x4 Air Filters BUY NOW
• Scroll to all AC Filter Sizes in Chart Now

First understand Air Filters, Furnace Filters, Ac Filter and Air Conditional Filters are all the same filters. So when if need to find home air filter sizes, HVAC filter sizes, furnace filter sizes or ac filters size or air conditioner filter sizes you are looking at the same thing. Using the Atomic experienced checked Chart below as a furnace filter size finder makes it easy to find the correct filters size for furnace.

The Filters in the Size Chart are Generally the Standard Air Filter Sizes.(note some of these brands manufacture is multiple countries including the US.)

Scroll to Carrier Filters Sizes in Chart Now 

Scroll to Goodman Air Filter Size Guide in Chart Now

Scroll to Lennox Filters Sizes in Chart Now

Scroll to Furnace and AC Filter Sizes in Chart Now Instantly Improve Your Air Quality by Choosing the Right MERV Rating because your family deserves the best.

Watch the video for guidance on using the furnace filter size chart below and hear expert tips to make the right choice and avoid common mistakes.  

Based on Atomic Filters Experience these are the Most Popular AC Filter Sizes

The most common AC filter sizes and furnace filter sizes are the 16x20x1 air filter, 20x20x1 air filter, the 16x25x1 air filter and the 20x25x1 air filter. All of these ac filter sizes can be found in the air filter size chart. The chart is a furnace filter size finder just click on the filter sizes and you will see purchase options. Click on 16x20x1 air filter to see MERV 8 filters, MERV 11 filters and MERV 13 filters available in the ac filter sizes. These Common Size air filters are the Sizes which can usually be found easily at the big box stores like Home Depot, Walmart and Lowe's. 

The ac air filter and furnace air filter sizes chart includes furnace filters sizes for your furnace. Furnace filter sizes for standard (also know as standard AC and  furnace filter sizes) and hard to find sizes are included in the list with Actual sizes and MERV options. 

How to Super Charge Your Air Filter

Super Charge Your Air Filters(and Kill Viruses and Bacteria in Air and on Surfaces on Your Home)

You can proactively clean the air and surfaces in your home by adding an In Duct Air Purifier that creates supercharged particles. This is the same compound created by thunderstorms and waterfalls in nature and helps purify the air. Aerosolized ions are effective in reducing bacteria, viruses, odors, and other contaminants that exist in the air you breathe inside your home. This creates charged particles which will attract to other particle in the air for better filtration when using electrostatic filters. Check out the Iwave-R. Learn more about how these air purifiers work to purifier the air and surfaces in your home. 

To Watch Video on How to Find the Right Air Filter (Experience Checked)

For a Video that Walks you through the step to identify the correct air filter for your home or business HVAC system.

Find Your Brand

In addition to the Atomic brand air filters, we stock a large selection of the most popular Brands of filters including Carrier, Lennox, Honeywell, Aprilaire and many more. Each brand may have actual sizes and that are different from the Nomial Size(Size on the Label sometimes a rounded size) listed on the filters label. It important to make sure you choose a brand that has the correct Actual size(Measured Dimensions of the filter) for your system. See Lennox and Carrier filters below.

Find Your AC and Furnace Filter by Brand, Model Number and Size

Click the link for the brand to see the entire collection. Use the search to find your item by Model, Title or Size. Note Goodman furnace filter size are compatible with Totaline. Use the Goodman air filter size guide below to find your exact filter. Find Lennox Furnace filter sizes by Model number in the Air filter chart. Check out tips to find the right furnace filter for your needs.  (note some of these brands manufacture is multiple countries including the USA.)

Complete List of Air Conditioner / Furnace Filter Sizes with Actual Size and MERV ratings available

Listed in the furnace filter sizes chart below are the standard size 1 inch, 2 inch and 4 inch depth air conditioner filters for your AC, Furnace, HVAC at Atomic Filters. We also offer custom size filters. Select the size to see a collection of furnace filters for that size. Need to know more about MERV ratings check out our air filter knowledge page. Filter are usually listed by the Nominal Size which is a rounded number, based off of the true dimensions of the filter which are called the "actual size". 

Find Your Filter Easily

Enter The Filter Part Number or Size from Your Current Filter in the Search, for example, enter X8795 or 16x20x1 or 20x20x1.

Air Filters Home

When looking for the correct home air filter here are several questions you might have.

1. What are the Best home air filters?

The best home air filters is a relative question. You should get the highest MERV rated filter your HVAC system will support it you want the best air quality in your home. Newer Modern HVAC systems should all support at least a pleated MERV 8 rated filter which is around the minimum level you would want to protect your homes air quality. MERV 11 to 13 filters is recommended for allergy sufferers. Superior systems from Carrier and Lennox offer some of the best residential filters available at MERV 15 and 16 respectively.  

2. What do air filters do in a house?

The primary function of an air filters is to protect your HVAC equipment from damage that can occur from dust and debris accumulating on the coils.This can have an effect on the efficiency of your system causing higher energy bills and a shorter system life.

Newer systems air filters are not just focused on protecting the equipment but improving the air quality in your home which is one of the number one health concerns listed by the EPA, CDC and American Lung Association.

3. How Often do you change air filters in your home?

How often you change your home air filters depends on the type of air filter you have in your house and environmental conditions such as smoke, dust or construction. 

Generally here are some guides but it can vary by manufacturer.

1 inch flat air filter - change every 30 days

1 inch pleated air filter- change every 2 to 3 months

Whole house filters - change 6 to 12 months ( more frequent change for desert areas and High humidity tropical areas).

4. How much is an air filter for a house?

Cost on filters may depend on the size of the filters but here are some ballpark prices.

1 inch flat green fiberglass filters which are considered cheap air filters can cost less than $1 but may have no MERV rating meaning they do not protect the air quality.

1 inches pleated MERV 8 filters can be as little as $4.50 if bought in bulk such as a case of 6 filters but the cost is dependent on the size of the filter.

Whole House filters vary in price by manufacture and can range from $25 to well over $100.

Are higher priced furnace filters worth it? Better quality air filters not only protect your expensive HVAC equipment, but they help protect your air quality which is one of the top health concerns according to the EPA. Most better quality filter are sold with efficiency rating of MERV 8, MERV 11 & MERV 13.  

How Do I Find the Size of My AC Filter?

How do I know what size air filter to get?

You can usually Find the Size of Your Air Conditioner filter right on the size of the frame of the filter. Many filters also have a model number of the filter.

The Picture of this 12x12x1 inch air filter has the Nominal size which is the size by which air filters are generally sold. On the right of the filter it also includes the actual size of the filter which are the true measures dimensions of the filter by length width and depth. See air filter image with Nominal size in red box and actual size in orange box :

How do I know what size furnace filter to buy? Many filters have sizes listed on the frame with length, width, and depth in inches and cm. Some filters may have a model number where you can lookup the model number or compatibles for the model number. If you can not find a size or model number you can measure the filter and look it up on the Air filter size chart by actual size.

If there is no size on your current AC filter, you can measure the length width depth of the filter and the filter to find the Actual Size of your filter with the Corresponding Furnace Filter size in the Furnace Filter Size(Nominal Size) Chart.

What happens if your furnace filter is too big? When a filter is too big it tend to crush or crack on the sides which can allow air to go through the crack or around the filter where is was dented. This prevents proper filtration.

How Often Should I Change My AC Filter?

General pleated 1 inch AC Filters are changed every 2 to 3 Months Depending on use. Environments with  Smoke, heavy dust (ie Desert) or pets may need more frequent air filter changing.

When should a filter be changed? A filter should be changes when it is loaded with particulate as noted by NAFA(National Air Filtration Association).

When should a non pleated fiber glass air filter be changed? Cheaper flat fiberglass filters may require changing every 30 days and may even be labeled as a 30 day filter.

Do more expensive furnace filters last longer? Better quality pleated filters have more media which is a higher quality media for better filtration and usually last (90 day) 3 times longer than cheap woven fiberglass filters(30 days). 

When should a 4 to 6 inch wide whole house air filter be changed? Whole House AC Filters with a size from Approximately 3 to 6 inches in width can have a life spans as long as 6 to 12 months depending on environmental conditions. 

Is it OK to run a furnace without a filter? No. You should never run your system with out a filter. The filter was originally designed to protect you expensive HVAC equipment and secondly more recently for air quality. EPA studies of human exposure to air pollutants indicate that indoor levels of pollutants may be two(200%) to five(500%) times — and occasionally more than 100 times — higher than outdoor levels.

What is the Best Furnace Filter?

Answer: MERV 13 for 1 inch filters or MERV 16 for Whole House Filters.

The best furnace filter or AC filter depends on your HVAC system. MERV is a rating system designed by HVAC engineers(ASHRAE) to evaluate filter efficiency. The Higher the MERV Rating the more efficient the filter. If you have 1 inch return vent filters or a 1 inch filter in the furnace, a pleated MERV 13 filter is generally the highest rated filter available for your system. MERV 13 filters are high efficiency filters recommended for allergy suffers. MERV 8 is around the level that begins to protect air quality in the home. The American Lung Association recommends a minimum of a MERV 11 filter efficiency.

If you have a system that uses a whole house filter you may have an option from MERV 8 up to MERV 16 depending on your HVAC system if you have a system that has an option of a highly efficient MERV 15 filter such as Bryan and Carrier offer in there Germicidal Air Purifiers. Lennox has a MERV 16 Filter option as offer in the Lennox Pureair System which is among the highest efficiency residential filters available and is also recommended by Lennox as an upgrade to specific Carrier, Trion Air Bear, and Honeywell systems.

Is an expensive brand of air purifier necessary if you have allergies? A better Quality Air Filter with an efficiency rating of MERV 11 or MERV 13 can make a difference in air quality for allergy suffers and does not have to be expensive. The cost of a single 16x25x1 MERV 13 air filter may cost about $9.99 and last up to 3 months so the cost is only $3.33 per month.

A low quality woven or spun fiberglass air filter is made to protect the HVAC equipment and not meant to protect air quality. According to the EPA and CDC indoor air quality it 200% to 500% more polluted than the air outside. Higher quality air filters will remove smaller particles from the air stream more efficiently as the MERV ratting increases. Many allergy sufferers add a standalone HEPA Air Purifier in a bedroom to have better air quality when they sleep. Better quality 1-inch pleated filters have more media which is a higher quality media for better filtration and usually last (90 day) 3 times longer than cheap woven fiberglass filters(30 days). 

Do furnace filters have to be exact size? Yes. An improperly fit air filter can let air flow around the filter. This will prevent the filter from protecting the HVAC system equipment and will not filter or protect the indoor air for air quality.

What are Lennox MERV 16 Filter Sizes by Model?

What are Lennox MERV 16 Filter Sizes by Model
See MERV 16 Filters by Lennox and Maintenance Kits. Click your model to see full details or add to cart below.

X6672 - Nominal size 16" x 25" x 5" ( Actual size 15 7/8" x 24 7/8" x 4 3/8" )
X6666 - Nominal size 17" x 26" x 4" ( Actual size 16-5/8" x 26" x 4" )
X6675 - Nominal size 20" x 25" x 5" ( Actual size 19 7/8" x 24 7/8" x 4 3/8" )
X6669 - Nominal size 21"x26"x4" ( Actual size 20-3/4" x 25-3/4" x 3-3/4" )
X7935 - Nominal size 20"x20"x5" ( Actual size 19-3/4" x 19-7/8" x 4-3/8" )
X8788 - Nominal size 20" x 26" x 5" ( Actual Size: 20" x 25-1/2" x 4 3/8" )
X8789 - Nominal size 17" x 26" x 5" ( Actual 16.31" x 25.47" x 4.31" )
X8790 - Nominal size 20" x 21" x 5" ( Actual Size 20" x 20-5/8" x 4-3/8" )

How do I know what HVAC filter I need?

1. Check Actual Size: Air filters are labeled with the Nominal Size(varies by Manufacturer and Model) which can be a rounded number. For instance a Lennox X6670 filter has a Nominal Size of 16" X 25" X 5" but an Actual Size 15-3/4" X 24-3/4" X 4-3/8". A 16x25x5 from Lennox may not be compatible with a 16x25x5 model from another manufacturer because they may have a different actual size.
2. Measure Actual Size of your current filter. Use a measuring tape and find the LxWxD(Length, Width and Depth of your current filter)
3. Check compatibility by Model Number. Filters may have a list of Models from Various Manufacturers which are compatible with the filter you need. Beware many filters models number are very similar, double check the actual size(true measured dimensions of the filter) to make sure you have the right filter.
4. Find the Right Filter Rating: MERV(Minimum Efficiency Reporting Value) is a rating system for air filters create by ASHRAE(American Society of Heating, Refrigerating and Air-Conditioning Engineers) to measure the efficiency of air filters. Some companies use their own rating system such as Home Depot uses FPR(FILTER PERFORMANCE RATING) and 3M uses MPR(MICRO-PARTICLE PERFORMANCE).
5. MERV 8(comparable to MPR 600 and FPR 5) is a good level to begin to protect air quality in your home. MERV 11( Comparable MPR 1000-1200 FPR 7) and MERV 13(Comparable MPR 1500-1900 FPR 10) are used in superior commercial buildings and in homes with allergy sufferer. MERV 15 and MERV 16 are among the top residential air/furnace filters available.

Where is the filter on a furnace?

Furnace filters are generally in 1 of these 3 locations.
1. Filter can be located in a blower compartment right before the air handler.
2. Filter can be in a filter cabinet next to furnace between the return vent and the furnace equipment.
3. Filter can be in return vents inside the home usually behind a removable grill.

What happens if you put a furnace filter in backwards?

The filter should always be placed in the correct direction for the Air flow. Here is why.
1. Placing the filter in backwards may cause the filter to collapse resulting in air flow going around the filter. Many filters have a wire backing to prevent collapsing against the air flow. The filters first job is to protect the equipment from dust. Air flow around a filter can damage your system.
2. Air flow in the wrong direction of a filter can create a greater resistance causing a strain on your system. This can increase utilities and shorten the life of your system.

Find My HEPA Air Purifier Replacement Filter

If you use a room air purifier and need to replace your filter it important to find the the correct size replacement  HEPA filter. Honeywell, Hunter and Whirlpool all have multiple Room Air Cleaner models available, so it is important to check compatibility before purchasing a replacement. Listing of emplacement HEPA filters for sale  usually list compatible models in the description or the bullet points, so make sure to check compatiblity to insure you purchase the correct fitting HEPA filter for your Air Purifier. 

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