Photo of Window Air Conditioner in Room

Are you looking to get relief from the heat but don’t want to spend a ton of money on air conditioning bills?

If so, you’ve landed on the right page.

Below, you’ll discover everything you need to know about getting the best window air conditioner for your home so you can stay cool (and save money) all summer long.

In this free guide, we’ll show you what important things to look for when making a purchase, as well as what the best window AC unit is for every size room.

The truth is that there are many options out there to choose from and if you don’t know how to spot the subtle differences between each unit, you could end up wasting a lot of money buying a significantly under- or overpowered device.

So, keep reading to find out what the best device is for your home!

Use these links below to jump to a specific section of the page:

In a hurry? Here’s a glimpse of the two best products you can get.

If you’ve got a bit more time you can find the detailed reviews and buying guide below.

What’s More Efficient: Window Air Conditioners or Central Air Conditioning?

This is probably the most commonly asked question by homeowners when they’re considering the purchase of a window mounted AC unit.

Will it really cut your monthly energy bills or is central AC better for the long haul?

The short answer is yes, window units do come out on top, and here’s why…

Window AC Units Use Less Energy

Photo of Energy Guide with EERIf you were to look at the Energy Efficiency Ratio (EER) for the top selling whole-house air conditioners, you’d probably find an EER rating between 14-16, which is really great.

In contrast, the top rated window air conditioners have an EER range of 11-12.

While a lower EER rating is technically less energy efficient, you can’t look at this number in isolation when comparing these two types of cooling devices.

In fact, even though window air conditioners have lower EER ratings, they actually cost less to operate and use less energy on a per cooling degree and per square footage basis by a factor of 1.75.

How can this be? There are several reasons:

  • People who use window AC units only cool down one or two rooms in a home, while those with central AC cool down all the rooms within a house, even the ones that are unoccupied.
  • Many central AC units have ducts in unconditioned attics, which can result in a loss of about 20% of their cooling output.
  • Central AC often gets left on by mistake because it’s out of sight and out of mind. Window mounted AC devices are always visible and people are more conscious to turn them off when not in use.

Actual Cost Savings

So, how does this all stack up in regards to monthly savings on your energy bills?

A central air conditioner costs between $100-200 per month depending on the amount of use.

You can expect to pay only $20-30 per month when using any of the window-mounted air conditioners we recommend below at a rate of eight hours per day.

How to Choose the Right Size Air Conditioner

One of the biggest mistakes you can make when buying a window AC unit is not getting one that’s properly sized for the room you want to cool.

It’s fairly common for people to unexpectedly buy a device that’s under- or overpowered for their intended use.

  • An underpowered unit may seem like a better deal because of its lower sticker price, but it will actually cost you a lot more to operate each month. Not adequately cooling a larger room will mean that it has to run more often, which increases your monthly energy costs.
  • An overpowered device will cost more to purchase up front than you really need to spend. It will also cycle on and off too much, which also wastes energy, increases electric bills and strains the unit.

The most cost-effective and efficient thing you can do is get the best window AC unit that’s designed for the size of the space you plan to use it in.

Here’s how to do it…

First, Measure the Square Footage of the Room

Graphic of How to Measure Square FootageTake a tape measure and measure the length and width of the room you want to put an AC unit in. For odd lengths, round up or down to the nearest whole foot number.

Then multiply these two numbers together. This will give you the square footage of the room.

Here’s an example…

For a room that is 12 ft. 6 in. long by 11 ft. 2 in. wide, we would round these two lengths to 13 ft. by 11 ft, then multiply them together.

13 x 11 = 143 sq. ft.

Next, Find the Correct Cooling Capacity

Once you have the square footage for a room, you can easily figure out what the proper cooling capacity is for an air conditioner. Cooling capacity is measured in BTUs, which is the international measurement for energy.

Below is a cooling capacity chart from Energy Star, which is the top resource for energy efficiency product information. If you take our previous example of a 143 sq. ft. room, the correct air conditioner would be one with a 5,000 BTU rating. (Our #1 recommendation lower on this page shows you which is the best AC unit in this class.)

Room Area To Be Cooled (square feet)Capacity Needed (BTUs per hour)
100 up to 1505,000
150 up to 2506,000
250 up to 3007,000
300 up to 3508,000
350 up to 4009,000
400 up to 45010,000
450 up to 55012,000
550 up to 70014,000

Note: If a wall divides any part of adjacent rooms then they are thermally separated. You may think that you can just buy a more powerful machine and expect that it will efficiently cool more than one room at once, but this is not true. When cooling multiple rooms you’ll want separate units for each room.

For example, a 14,000 BTU can cover 700 sq. ft. However, a window air conditioner of this caliber won’t work for 500 sq. ft. living room and 200 sq. ft. bedroom that are next to each other, even though these two combined equal 700 sq. ft.

You would actually want to buy a 12,000 BTU unit for the living room and a 6,000 BTU unit for the bedroom in order to maximize energy efficiency and have the lowest monthly electricity costs.

Other Important Features to Look For

When shopping for the best window AC for your home or office, you’ll find a variety of additional features that manufacturers include with their particular device.

Some of these options will matter a great deal to you, while others won’t.

Obviously, the more features a product has, the more expensive it will cost. However, just keep in mind that as long as the BTU capacity is sized correctly for the room you want to use it in, then you’ll achieve maximum efficiency no matter what other perks it may have.

Here are the top things you’ll find as you compare air conditioners:

Cooling Speeds

This is the most basic feature on all air conditioners, but different manufacturers choose to include a different number of cooling speeds.

Most commonly you’ll find products to have either two or three cooling speeds. These come in High, Medium and Low settings.

Temperature Control Options

Although we live in the digital age, there are still many window AC units that use a rotary dial for controlling the temperature. You’ll see these dials labeled with numbers such as 1-7, with the highest number being the coldest setting.

With a dial style unit, you won’t be able to choose a specific degree setting, but rather must rotate the dial until it feels like the right temperature in the room. (Our #1 best window air conditioner below uses this type.)

The more advanced window air conditioners include electronic push buttons and an LCD screen, which gives you precision control over the temperature. This handy feature allows you to set the unit to a specific cooling degree, such as 72 degrees Fahrenheit, and have it be maintained by the device.

(Our #2 and #3 recommendations come with this option.)

Air Direction Control

When you’re looking at window air conditioners, you’ll find a wide range of options for much you can control the direction of the air that’s produced by the unit.

Some devices only offer 2-way air direction control (left to right with one vent), while others give you up to 8 ways to adjust it (left to right and up to down with two separate vents).

Although 8-way control may sound nice, it’s actually one of the least things you should worry about. Once the room is cooled down by the AC unit, it doesn’t really matter what direction the air is entering the room.

This feature is really only important for people who don’t want the air blowing in a certain direction that would become an annoyance. This includes places like toward a dinner table or directly on you while you sleep.

Automatic Timer

If you want to save the most amount of money while keeping your rooms cool, an automatic timer is a must-have feature for your device.

Automatic timers allow you to control when the air conditioner turns on and shutoffs without having to manually do it yourself.

For example, you can set it to turn off automatically after three hours of continuous use or between specific hours like 9 a.m. to 5 p.m. Some timers even let you turn the device on at a certain time of day, such as one hour before you get home from work so that the room is nice and cool before you arrive.

(Our #2 and #3 recommendations below include this feature.)

Air Cleaning Functions

All rooms have impurities floating around inside them. The most common elements include dust, mold, bacteria, pollen, smoke, and odor producing particles.

Some of the top rated window air conditioners are outfitted with air cleaning filters that remove these impurities from the room so that they don’t make you sick or affect your health.

Often, you’ll find either a washable antibacterial filter or an air ionizer function that sends out negatively charged ions into the air to neutralize these harmful particles. Both of these options clean the air, but the air ionizer is much better at it.

If you want cleaner, fresher air while cooling it at the same time, air purification is a great feature to look for in a device.

(All three of our product recommendations below include this feature.)

The Three Best Window AC Units You Can Buy

Now that you know what to look for in a window AC unit, here are the best products you can buy for each size room: small, medium and large.

Frigidaire FFRA0511R1 5,000 BTU Window Air ConditionerPhoto of Frigidaire FFRA0511R1

For Small Rooms

If you’re looking to get the most affordable and efficient window AC unit on the market, then this is it.

Not only has it received more than 1,600 positive reviews, but its one of the highest quality devices in its class.

With 5,000 BTUs, it can handle a space up to 150 sq. ft. and is perfect for many home applications.

The rotary dials, two cooling speeds, and 2-way air direction control are standard features at this level. Digital controls just don’t exist.

The most amazing feature, however, is the washable antibacterial filter. This filter cleans the air by removing harmful bacteria and odor particles while you enjoy cooling comfort.

See Reviews

Frigidaire FFRE0833S1 8,000 BTU Window Air ConditionerPhoto of Frigidaire FFRE0833S1

For Medium Size Rooms

If you want to cool down a space like a living room or large bedroom, then this is the product that you want to get.

It’s rated to handle a space up to 350 sq. ft. and has the most versatile features out of any other 8,000 BTU product on the market.

With this device, you get precise control over the temperature degree setting, as well as three fan speeds, 8-way air direction control, and a handy timer function. It even comes with a remote so you can make adjustments from anywhere in the room.

Similar to our first recommendation, this unit also has powerful air cleaning functionalities.

However, instead of using a filter to remove impurities from the air, like pollen, dust and bacteria, it has the upgraded feature of using an air ionizer. This option makes it a great investment for anyone who suffers from allergies and wants to breathe cleaner, fresher air while also enjoying a cooler room.

See Reviews

Frigidaire FFRE1233S1 12,000 BTU Window Air ConditionerPhoto of Frigidaire FFRE1233S1

For Large Rooms

Out of all of the products on the market that are made for large sized rooms, this is the very best window mounted air conditioner around.

It has everything you would ever need in an air conditioner, including an LCD screen with precise temperature control buttons, three cooling speeds, an automatic timer, remote control and 8-way air direction control.

Additionally, it has both an air ionizer and washable filter to strip the air of as many harmful particles as possible. It’s a dream come true for asthma and allergy sufferers who require the freshest, coolest air they can get.

You won’t find anything else that can beat this device in this price class.

See Reviews

Why is Every Top Rated Window Air Conditioner On Our List a Frigidaire?

If you made it this far in this post, you may be wondering why all of the top window air conditioners are Frigidaire models and not a mix of something else.

Are we biased? Of course not.

The truth is that there are many other manufacturers of window AC units, including Emerson, Friedrich, GE, LG, Kenmore, SPT, Whirlpool, etc.

But, when it comes down to the customer reviews, price, value and available features, Frigidaire is the clear winner on every front.

We’d love to recommend other manufacturers for having the best window air conditioner, but at this time we can’t.

Other models may have the same exact features as a Frigidaire , but come with a higher price tag. Or, the price may be the same, but they lack something that Frigidaire includes, like the air ionizer feature.

You won’t go wrong by getting any of these Frigidaire models we recommend above. They truly do make the best window AC unit for every size room. Feel free to look at the reviews yourself and choose the one that’s best for your needs.