The Best Air Conditioners of 2025, Tested and Reviewed

Nothing feels quite like the sweet relief of turning on your AC on the first hot day of the year. In addition to having a decade of experience covering heating and cooling appliances, I’m also someone who hates being hot, so crisp, refreshing AC is something I’m personally passionate about. To find the best air conditioners, I talked to HVAC experts and tested over 20 units to see how effective, quiet, and energy-efficient they are.

Our top pick is the Frigidaire Gallery GHWW085TE1, which is one of the quietest and most efficient ACs we’ve ever tested. It replaces the Midea U Inverter Window Air Conditioner as our top pick, which was recently voluntarily recalled because its U-shaped design (which allows you to open your window even with the AC installed) led to mold issues in some units. Midea confirmed to Business Insider that new units being sold have been repaired to fix the issue. We’re planning on testing one of these repaired units before we reconsider the Midea U for the top spot.

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 portable air conditioners versus window air conditioners guide details the differences between these styles if you’re unsure which is best for your needs.

Learn more about how Insider Reviews tests and researches home products.

The best air conditioners

Best overall: Frigidaire Gallery GHWW085TE1 – See at The Home Depot

Our former top pick (still great): Midea U MAW08V1QWT – See at Amazon

Best for large rooms: Frigidaire FHWW145WE1 – See at Frigidaire

Best portable: LG Smart Wi-Fi LP1419IVSM – See at Best Buy

An easy-to-install option for city dwellers: July Air Conditioner – See at July

Best overall

The Frigidiare Gallery led the pack in nearly every test we performed. On high, this AC dropped the temperature in my bedroom by 10 degrees over eight hours. By the time I went to bed, my room was a frosty 63 degrees. For those who don’t need to sleep in an igloo like I do, the unit has three fan speeds and an eco mode to choose from.

It’s so quiet that I sometimes forget it’s on. On high, it registered at 47 decibels, which is quieter than any AC we’ve tested. The sound is incredibly smooth, too. It’s just one consistent woosh with no interruption or rattling.

Despite its superior cooling, it’s still incredibly energy efficient. It’s one of the few units to receive Energy Star’s “most efficient” award. In my tests, it clocked in at 0.46 kWh after an hour of use, just 0.06 more than the Midea U. Assuming about eight hours of use each day, it’ll cost me just $51 to run this AC all summer.

Its energy efficiency and low noise output are owed to its inverter technology. Inverter compressors have variable-speed motors that adjust to maintain the desired temperature. This constant low-level operation is more efficient and quieter than cycling high output on and off like traditional units do.

A unique feature is its air quality sensor. A light on the front of the unit changes between green (good), yellow (not so good), and red (bad), depending on the air quality of the room. I notice it switches to red when I’m burning a candle or cooking. The AC alone won’t do anything to improve the air — you’ll need an air purifier or Frigidaire’s PureAir allergen filter (currently sold out) for that. Still, it’s a nifty reminder of the effect actions have on indoor air quality.

I don’t like that you can’t turn the air quality indicator light off. I’m a super sensitive sleeper, so having a bright light on in my room all night is a no-go. The only option for turning it off is the AC’s “sleep mode.” Unfortunately, this setting also raises the temperature 4 degrees over the course of the night to conserve energy, and I woke up feeling hot when I tried it out. I ended up covering the light with a strip of construction paper; it works, but also ruins the otherwise pleasant aesthetic of the AC. —Lauren Savoie, deputy executive editor

Our former top pick (still great)

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 owed to its U-shaped design, which keeps more of your window accessible for some fresh air and more light. Unfortunately, the very design that made it so innovative also caused it to accumulate mold, and in the spring of this year, Midea recalled the units. We noticed Midea recently began selling the U again, and we confirmed with reps from the company that these units have been repaired to fix the recall issue. We demoted it from the top spot in this guide while we test the new units, but we still think it’s a worthwhile AC.

Like the Frigidaire, the Midea U uses inverter technology to achieve impressive efficiency numbers. It’s the first window AC to receive the Energy Star “Most Efficient” certification and remains one of only a few models to receive that designation. 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 51 cents to run it for an eight-hour day.

Installation was quick, though the instructions could be a bit clearer. Still, I had the unit up and running within 25 minutes of opening the box. Connecting to the smart app was also quick, and I could control the Midea U with my voice using Alexa.

I was impressed with how quietly the AC runs. The sound meter registered 48 decibels while it was operating at its highest setting.

The Midea U decreased the test room’s temperature by 1.7 degrees in the first hour, which is impressive considering its energy efficiency.

Read my full Midea U-Shaped Air Conditioner review.

Best for large rooms

Large rooms require an air conditioner with enough Btu to keep you cool — this one 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 AC is one of the most powerful air conditioners I’ve tested, dropping the testing room’s temperature by four degrees in one 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, the electricity cost will be about $1.56 on average for an eight-hour day.

It’s not the quietest we’ve tested, but it’s noise levels are decent. I use this air conditioner on the first floor of my house, which is about 1,500 square feet. I’ve installed it in the living room, where we do most of our TV watching. When I run it in Eco mode, I have no trouble hearing my shows. It’s also kept me plenty cool, even during the muggy Michigan heat waves.

The Frigidaire FHWW145WE1 was a breeze to install, taking 10 minutes to install and five more to pair with the Frigidaire app. 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. 

The smart functions are pretty basic. 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.

Best portable

If you have a window that will accommodate it, I always recommend a window unit over a portable model. Portable ACs vastly underperform compared to window ACs, and no portable models are Energy Star certified. While window AC units suck in hot air and vent it directly out the window, portable ACs rely on a long tube to carry air from your room to the outside. Along the way, heat radiates from the tube and stays in the room, and the pressure differential from removing the hot air attracts more hot air. It takes a lot more energy (and money) to cool a room with a portable AC than a window AC. 

If a window unit is not an option, the LG Dual Inverter Smart Wi-Fi (LP1419IVSM) is your best bet.

The LG portable AC is the top pick in my guide to the best portable air conditioners because it’s quieter and more efficient than most models due to its dual-inverter compressor. Based on average electricity rates, it costs about 85 cents to run for an eight-hour day. It’ll take about double the time to cool a room than a window unit, but it’s very easy to install and use. 

After an initial 30-minute installation time (including connecting to the app), moving from room to room was super simple. Thanks to its handles, smooth casters, and a dedicated slot for the window slider when in transport, it only took about a minute to reinstall it in a new room. We like that it can accommodate a wider range of windows than the other units in this guide.

It’s Alexa-enabled and also has smart capabilities through the LG ThinQ app, which lets you schedule when the unit runs.

Read our full LG portable air conditioner review and check out our guide to the best portable air conditioners.

A great option for city dwellers

The July was the safest and easiest AC install we’ve done. For those who live in multi-story apartments, AC installation can be a harrowing — and dangerous — experience. July makes the process much easier by having you first install the unit’s border and side panels securely into the window. Then you pop the AC unit in — the frame ensures there’s no risk of accidentally dropping your AC out the window. The process took 15 minutes, and another five minutes to download and connect to the July app. In addition to the usual array of features, the app lets you set a schedule. I paired it with Amazon Alexa for voice control.

It’s very aesthetically pleasing and can do double duty as an air purifier. While most air conditioners are boring-looking at best and an eyesore at worst, the July Air Conditioner features an aesthetically pleasing, minimalist design and six cover options to match your home’s decor. You can also add plexiglass side panels for extra natural light, which is a boon for city-dwellers who pause at the idea of sacrificing their one good window to an AC all summer. For $30 extra, you can also add on an air purifying filter, which eliminates the need to keep another bulky appliance around and might make you feel a little better about breathing in the city air.

Performance-wise, the July air conditioner was a little better than average. It decreased the room temperature by two degrees in an hour, which is good considering the test room was 2.5 times as big as what it’s rated for.

The noise and energy use were middle-of-the-pack. In an hour, the July used 0.5 kWh. Based on average electricity costs, it will cost you about 64 cents to run for eight hours. The unit was about 55 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.

Read my full July Air Conditioner review.

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 split, and through-the-wall units.

• Window ACs: This guide primarily deals with window air conditioners because they’re relatively inexpensive, easy to install, and can be used by both renters and homeowners. I think this is the best for most people.
• 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 does not have 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 how much heat is removed from a room. The more Btu per hour an air conditioner is rated for, the better job it does 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 the moisture, which will create 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 denotes 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 that allows 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, offered with all ACs in my guide.
• Noise: All AC units make some noise, but if you’re installing a unit in a bedroom, you want to keep sound output consistent and at 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 when the AC is installed. This is a nice option if you live somewhere where the weather fluctuates a lot during the season. Another model, the July Air Conditioner, has the option to add clear side panels to let in more natural light. 

How we test air conditioners

I tested 14 window units and consulted Enesta Jones, an EPA spokesperson, to determine the best air conditioners. My picks are energy-efficient, have helpful features, and performed well in my tests.

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 it took to install each model, noted if 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 determined its cooling capabilities by comparing the temperature before and after running the AC on 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 the particulate matter and volatile organic compounds in the air before and after running the AC for an hour. I noted any significant changes in air quality in my reviews, but the air quality 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 of power each unit used when 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.

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 access 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.