Best air conditioners

A punishing heat wave is upon us, and if history is any indication, standard delivery windows and store shelves are about to clear out fast. Waiting until your living room feels like an oven to buy an air conditioner is a recipe for weeks of miserable, sleepless nights, and potentially dangerous indoor temperatures. It's not just a matter of staying cool; air conditioning has become a necessity.

To help you beat the heat, we've rigorously tested over 20 window and portable units. We evaluated them for raw cooling speed, energy efficiency, decibel levels, and ease of installation. Keep in mind that you'll need single- or double-hung windows to properly install a traditional AC. All other window types will benefit from the best portable air conditioners. Our story on portable versus window air conditionersdetails the differences between these styles if you're unsure which is best for your needs.

The best air conditioners

Best overall air conditioner: Frigidaire Gallery GHWW085TE1 - See Amazon

Best U-shaped: Midea U-Shaped Inverter Air Conditioner - See at Amazon

Best portable air conditioner: Midea Duo Smart Inverter Portable Air Conditioner (MAP14S1TBL) - See at Amazon

Best air conditioner for large rooms: Frigidaire 14,000 BTU FHWW145WE1 - See at Frigidaire

Best design: Windmill Air Conditioner - See at Windmill

Best overall combination of cooling, low noise, and energy efficiency

Our top pick crushed it during testing. The Frigidaire Gallery led the pack in nearly every test we performed. On high, it lowered my bedroom temperature by 10 degrees over eight hours, bringing the room to a chilly 63 degrees by bedtime. For those who don't need to sleep in an igloo, it offers three fan speeds and an eco mode.

It's also the quietest AC we've tested and one of the most efficient. On high, it measured 47 decibels with a smooth, steady whoosh and no rattling or cycling noises. It's also one of the few window ACs to earn Energy Star's "Most Efficient" designation. In my tests, it used 0.46 kWh after one hour, just 0.06 kWh more than the Midea U. Based on eight hours of daily use, I estimate it would cost about $51 to run all summer.

Much of that performance comes from its inverter compressor. Unlike traditional compressors that cycle on and off at full power, inverter compressors use variable-speed motors to maintain the set temperature at a lower, steadier level. That helps cut down on both noise and energy use.

The built-in air quality sensor is useful, but its indicator light is my biggest complaint. A front-facing light changes from green to yellow to red based on the room's air quality, and I noticed it turned red when I burned a candle or cooked. The AC itself won't significantly improve air quality — for that, you'll need an air purifier or Frigidaire's PureAir allergen filter — but it's a helpful reminder of how everyday activities affect indoor air. Unfortunately, the light can't be turned off independently. The only option is sleep mode, which also raises the temperature by 4 degrees overnight to save energy. I woke up hot when I tried it, so I covered the light with construction paper, which worked but detracted from the AC's otherwise sleek design.

A design that doesn't block access to your window

You can actually open the window when using this unit. The Midea U was the first AC to offer a true innovation over the classic window unit design: the ability to open the window while it's installed. This is due to its U-shape, which keeps more of your window accessible for fresh air and natural light.

However, that groundbreaking design had a major flaw, but the 2026 redesign works to address it. Units sold between 2020 and mid-2025 were prone to internal moisture pooling and black mold accumulation if they weren't installed at a flawless angle, resulting in a product recall. Midea initially addressed this by sending out manual rubber drain plug repair kits, which we tried ourselves, but the current2026 generationfixes the issue with a hardware redesign, featuring integrated external foot levelers to ensure foolproof sloping and an open rear drainage hole so condensation can escape. The current edition also tacks on a dedicated dehumidifier mode, an improved dust filter, and a longer two-year warranty.

Note: If you want the 2026 model, be sure to compare the product numbers, as it gets tricky. The 2026 version is MAW08V1UWT versus the updated model with the repair kit is MAW08V1QWT.

Installation remains a hurdle. Because of its split-chassis design, setting up the Midea U is significantly more involved than standard units. Instead of relying on built-in accordion folds, you have to secure an independent support bracket into your window sill, slide the heavy unit onto it, and meticulously cut and stuff foam blocks to seal the gaps. While our previous expert tester knocked it out in 25 minutes, it took me a full hour—mostly because I was obsessively checking that the unit was perfectly level to prevent any future mold issues. It also leaves you with a drawer full of specialized, alternate window brackets and accessories that you'll have to store if you move often. City dwellers should also note that if your high-rise building uses pre-installed, mandatory exterior safety brackets, you may have to creatively DIY the Midea bracket to fit around them.

Once it's in, the performance is stellar. Like the Frigidaire, the Midea U uses inverter technology to achieve impressive efficiency numbers. It consumed 9.6 kWh over a 24-hour period, which works out to 0.4 kWh each hour. Based on average electricity rates, it will cost you about 55 cents to run it for an eight-hour day. I was also impressed with how quietly the AC runs. The sound meter registered a smooth, non-disruptive 48 decibels at its highest setting.

Read our full Midea U-Shaped Air Conditioner review.

A surprisingly powerful portable AC

If you don't have space for a window AC, this is the model we recommend. Portable ACs inherently underperform compared to window models. Because they rely on a long exhaust tube, heat radiates back into your room from the hose, creating a pressure differential that draws in outside air and forces the machine to work twice as hard. If a window unit is not an option, the Midea Duo is your absolute best bet because its unique hose-in-hose design stops that hot air leakage.

It's the most powerful and quiet unit I tested, but that comes at the expense of energy usage. In testing, the Midea Duo reduced the temperature of a 550-square-foot room by 3.3 degrees Fahrenheit in two hours, one of the best performances I've seen. On low, the Midea Duo runs at just 43 decibels, which is five decibels quieter than any other unit I tested, and maxes out at 56, which isn't too disruptive either. However, the Midea used 2.16 kWh over an hour, about 0.2 kWh more than the overall hourly average in our tests.

It's easy to control with the accompanying app. Fortunately, you can offset those energy costs using Midea's feature-packed SmartHome app. The app allows you to set a customized "sleep curve" that balances overnight comfort with power usage, control the airflow direction, and pair the unit with Amazon Alexa or Google Assistant for voice commands. I choose to schedule the Midea to turn off during peak electrical pricing and come back on afterward to ensure the room is comfortable by bedtime. You can also turn off the LED display to avoid light pollution.

The Midea Duo is also available with a heating mode, though we haven't tested this model. Read our full Midea Duo Smart Inverter Portable Air Conditioner review.

A great option for large rooms

Large rooms need powerful ACs — and this option from Frigidaire delivers. With 14,000 Btu of cooling power, it can comfortably handle lofty and open spaces. The AC features an inverter compressor that adjusts its speed to maintain the room's target temperature rather than just turning off and on, as most ACs do. The Frigidaire FHWW145WE1 is one of the most powerful air conditioners I've tested, dropping the test room's temperature by 4 degrees in 1 hour.However, it was also one of the loudest units I've tested and used the most electricity. Fortunately, it features an Eco mode that balances noise, power use, and cooling.When running it on high, electricity costs will average about $1.56 for an eight-hour day.

It's super easy to set up. I was especially impressed with the seamless installation, considering our previous best air conditioner for large rooms pick, the discontinued LG LW1517IVSM Dual Inverter Smart Window Air Conditioner, took two hours to install and aggravated my chronic back pain with its 100-pound weight.

It has basic smart features. You can change the temperature, mode, and fan speed. Plus, you can set schedules, so the AC automatically turns off when you aren't home or during your utility's surge pricing hours. Overall, this is an outstanding choice for cooling large rooms.

A stylish design that's also easy to install

If you want to balance aesthetics with cooling, this AC is for you. While most air conditioners are boring-looking at best and an eyesore at worst, the Windmill Air Conditioner features an aesthetically pleasing, minimalist design. Side panels hide the ugly accordion folds, so the unit looks like an extension of your walls.

It took minutes to install. The Windmill comes with everything you'll need to get it into your window, including a pair of scissors. The process took our installer just 10 minutes from start to finish. You can control the AC via discreet buttons on the top of the front panel, a remote, or the Windmill app. The app even has features we haven't seen in other ACs, like the option to set the air temperature to track the sun's position.

It has average noise levels and efficiency. In an hour, the 12,000 Btu version of the Windmill used 0.67 kWh. Based on average electricity costs, it will cost you about a dollar to run for eight hours — and less if you opt for a less souped-up Btu model. The unit was about 54 decibels on high speed, or a little louder than a refrigerator. Overall, this is the best air conditioner you can buy if aesthetics and easy installation are major considerations.

It also has air purification. For about $45 extra, you can add on a pack of air purifying filters, which eliminates the need to keep another bulky appliance around and might make you feel a little better about breathing in the city air.

Read our full Windmill Air Conditioner review.

Our top picks compared

What to look for in an air conditioner

When shopping for an AC, there are four primary factors to consider: type of AC, Btu, energy efficiency, and extra features. Below, I detail more about what to look for in each category:

Types of air conditioners

There are four primary types of air conditioners: window units, portable air conditioners, ductless mini-splits, and through-the-wall units.

• Window ACs: This guide primarily recommends window air conditioners because they're relatively inexpensive, easy to install, and suitable for both renters and homeowners. I think window ACs are the best for most people if central AC is not an option.
• Portable ACs: You may consider a portable air conditioner if you don't have windows that will fit a traditional unit. However, they're less efficient at cooling than window units. Read more about the best portable air conditioners and when you should buy a window AC vs a portable AC.
• Ductless mini-split air conditioners: Mini-splits are a more permanent cooling solution. They feature a wall unit connected to a compressor that sits outside your home. We only recommend this AC type for homeowners who do not want to invest in a full HVAC system.
• Through-the-wall ACs: These units should only be considered when you're aiming to cool a room with an exterior wall that has no windows, or if this is the type of unit already installed in your home or rental.

Btu

Btu is short for British thermal units. One Btu is equal to the amount of heat needed to raise 1 pound of water by 1 degree Fahrenheit. In cooling, Btu is used to measure the amount of heat removed from a room. The more Btu per hour an air conditioner is rated for, the better job it does of cooling. That said, you shouldn't just leap to buy the air conditioner with the highest Btu possible. For maximum cooling and efficiency, you need a unit that isn't too big or too small for your room size.

If you get a unit that is too big for your room, it will cool too quickly without removing moisture, creating a cold, clammy environment. Alternatively, an AC that is too small will be overworked, boosting your energy bills. Use the table below (from the Energy Star website) to determine the best air conditioner Btu for your room size:

Your Btu needs will be greater if the room has a ceiling more than 8 feet high, is very sunny, is regularly occupied by more than two people, or it's a kitchen.

It's common for model numbers for the same units to vary by one or two digits. This usually indicates different Btu ratings and colors, so choosing a model number that reflects the Btu rating right for your room is crucial.

Energy efficiency

Air conditioners have come a long way in terms of energy efficiency, but you'll want to look for a few things that will ensure you're getting the most efficient unit possible:

• Energy Star certification: The easiest way to determine if you're getting an energy-efficient appliance is to look for Energy Star certification. This program is run by the US Department of Energy and EPA to promote energy efficiency. "Any window AC model that earns the Energy Star label is independently certified to save energy, save money, and help protect the climate," says Enesta Jones, a spokesperson for the US Environmental Protection Agency (EPA). The EPA oversees the Energy Star program.
• CEER: If you want to get deeper into the numbers, look at a unit's CEER. "The CEER, or Combined Energy Efficiency Ratio, is a measure of energy efficiency for a room air conditioner," Jones says. "The higher a room air conditioner's CEER value, the more efficient the room conditioner is when comparing across models with the same cooling capacity." The CEER is measured by dividing the Btu output by the amount of energy consumed both while the unit is running and while it's in standby mode.
• kWh: Finally, consider kilowatt-hours (kWh). This is a unit of energy that most electricity utilities use to measure your power use, and it's what I use to measure the energy consumption of the air conditioners I test.

Extra features and other considerations

Below are some other features and qualities you might consider when shopping for an AC:

• WiFi connectivity: Some ACs have WiFi connectivity, allowing you to use your phone to schedule and control the unit remotely. You can crank the AC before you get home or turn it off after you leave to save energy. Many pair with smart speakers for voice operation. Smart ACs don't always work as advertised. In my reviews, I note if smart functions work well. In general, though, you're probably better off using a remote control, which is included with all ACs in this guide.
• Noise: All AC units make some noise, but if you're installing a unit in a bedroom, you want to keep sound output to a minimum. I note the noise output of the picks above.
• Window access: Some newer AC models (notably the Midea U) offer window access even after installation. This is a nice option if you live somewhere where the weather fluctuates a lot during the season.

How we test air conditioners

Our testing methodology

Here is how I test the main attributes I look for:

Installation: You'll probably only install and uninstall your AC once a year, but it can significantly impact your unit's performance. I timed how long each model took to install, noted whether I needed special tools, and assessed how easy it was to uninstall. I also looked at the window sizes each air conditioner would fit. Most will fit windows 27 to 36 inches wide.

Cooling: I set up a digital thermometer on the opposite side of a 650-square-foot room from the air conditioner and measured its cooling performance by comparing the temperature before and after running the AC at its highest setting for an hour.

Noise: I took a decibel reading using a sound meter positioned 6 feet away from the AC running on high. I also noted any jarring sounds as the compressor turned on and off.

Air quality: Using an air quality monitor, I measured particulate matter and volatile organic compounds before and after running the AC for an hour. I noted any significant changes in air quality in my reviews, but it never entered the "harmful" range during the tests, and I don't weigh this category heavily.

Power use: Using a smart plug, I measured how many kWh each unit used while on high for an hour.

Extras: Almost all ACs have fan and dehumidifier modes, a window installation kit, a delayed on/off function, and a remote control. These are the basics. I give extra points if a unit has foam seals, curtain insulation, WiFi connectivity, or other bonuses.

Meet the experts behind the guide

James Brains, former senior reporter: I tested 14 different air conditioners for this guide with a series of objective tests. I use my testing results to make recommendations for every type of person, whether you need a budget-friendly window unit or a portable AC.

Lauren Savoie, former deputy editor: I completed an additional round of testing with new releases to update our list of the best air conditioners. I used James' methodology for consistent results.

Air conditioner FAQs

How can you use your air conditioner efficiently?

Jones recommends you keep the unit level, circulate cool air with a fan, keep heat-producing objects away from the AC thermostat, and use a low fan speed on humid days. You can also save on energy costs by installing your air conditioner in a shaded spot and keeping the thermostat as high as is comfortable.

Can I use an air conditioner in a room without windows?

Yes. However, the hot air your AC produces needs a way out of the room. Otherwise, you'll cancel out your unit's cooling effects. If you don't have a window, pick an AC that sends its hot air out the back. You can install these in an exterior wall.

A portable unit gives you more options since the opening to the outdoors only needs to be as large as the exhaust hose.

Which is better: a portable air conditioner or a window/room air conditioner?

I cover this topic extensively in my comparison of portable air conditioners vs window air conditioners, but the short answer is: window units, for most people.

According to Jones, window ACs are more efficient than portable units, which aren't part of the Energy Star program. I found this to be true in my testing. The most efficient portable AC I tested used 60% more energy than the top window pick.

Portable ACs are great in spaces where there isn't a window that can support a window air conditioner. But, in general, if you have a single- or double-hung window, the best air conditioner is a window unit. It will offer better cooling and efficiency along with lower upfront and long-term costs.

What should you do if your air conditioner is too powerful for your room size?

If your AC has too much Btu for your room, it will cool faster than it can dehumidify, creating an uncomfortable, clammy environment. Consider purchasing a dehumidifier to remove excess moisture or replacing the AC with a more suitable unit. Another solution is increasing the space you are cooling. You can do this by keeping internal doors open.

How do you clean an air conditioner?

The most frequent maintenance task on your air conditioner is cleaning the filter. This should be done once or twice a month and is pretty simple. Just remove the filter, use a handheld vacuum to remove any debris, then wash it with soap and water, allowing it to dry completely before reinstalling it.

You should clean your AC's coils, fins, interior, and exterior every year. For details on how to do that, visit my article on how to clean window air conditioners.

What's the best air conditioner for a bedroom?

When shopping for the best air conditioner for a bedroom, look for an option with low noise levels, dimmable displays, and mid-range power. Our top pick is an excellent option for bedrooms, though you'll have to cover the air-quality light if you're bothered by lights at night.

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