The 7 Best Air Conditioners of 2021

Enjoy a cool, comfortable summer

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Best Air Conditioners

The Spruce / Chloe Jeong

Keeping your living space cool during the summer months can make these days much more enjoyable. If you live in an area that gets warm temperatures, an air conditioning system is the most efficient way to keep your home comfortable. For those who have extreme temperatures, an air-conditioner is a must-have to ensure family and pets stay safe.

When considering which air conditioning system will work for you, think about the output that your space needs, the size of the space and installation area, and extra features like a quiet noise level that will make your home flow better overall.

Here are the best air conditioners to stay cool in hot temperatures.

Our Top Picks
Energy star certified, this unit has adjustable louvers so you can direct the cool air where you need it.
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This single room unit features adjustable side panels, washable filters, a 1-7 cooling scale, and two fan speeds.
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This portable air conditioner has many features to improve the air quality of a large space including the ability to cool, warm, and dehumidify.
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Best for Large Rooms:
Whynter ARC-14SH at Amazon
Free-standing, this unit can cool large rooms or small apartments, has two filters, and uses a CFC-free refrigerant.
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Portable and sleek, this unit has wheels which allow you to move it from room to room, and has cool, fan, and dehumidify modes.
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It can be controlled by using a remote, voice commands, on the unit itself, or by using an app through your smart home device.
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The noise level is up to nine times quieter than other models, and measures only 42 dBA on its lowest setting.
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Best Overall: LG Energy Star Rated 6,000 BTU Window Air Conditioner with Remote Control

LG 6,000 BTU Window Air Conditioner

Cooling Area: 260 square feet | BTU: 6,000 BTU | Noise Level: 49 dBA | Window Size: 27-39 inches | Remote Control: Yes | Energy Star Certified: Yes

What We Like
  • Energy efficient

  • Remote control

  • Adjustable louvers

What We Don't Like
  • Boxy design

This LG air conditioner window unit is the perfect solution for those who want to keep their power use down, both for the environment and their wallet, and their house's temperature down. It has adjustable louvers to direct the cool air where you need it and reduce the overall output required. You can control the three fan speeds and settings using the remote control or on the top of the unit itself. It is Energy Star certified and automatically turns off once the temperature is cool enough. I used this air conditioning unit to cool my bedroom in Hawaii, where energy costs are especially high. While it doesn’t have a lot of fancy features, it kept my room cool and my power bill low.

Best Budget: Midea 5,000 BTU Window Air Conditioner with Mechanical Controls

 MIDEA 5,000 BTU EasyCool Window Air Conditioner and Fan

Cooling Area: 150 square feet | BTU: 5,000 BTU | Noise Level: 54-57 dBA | Window Size: 23-36 inches | Remote Control: No | Energy Star Certified: No

What We Like
  • Budget-friendly

  • Multiple settings and speeds

  • Washable filters

What We Don't Like
  • No remote

  • Clunky design

This budget-friendly window unit from Midea delivers just what you need for small rooms without requiring a huge financial investment. It has two different fan speeds and a 1-7 cooling scale that are all adjustable. Installation is easy, especially with the adjustable side panels that allow this window unit to work with a variety of windows. The filters are washable, saving additional costs over the long term.  

Best Portable: SereneLife 12,000 BTU Portable Air Conditioner + Heater

SereneLife 12,000 BTU Portable Air Conditioner + Heater

Cooling Area: 325 square feet | BTU: 12,000 BTU | Noise Level: 56-59 dBA | Window Size: Free-standing | Remote Control: Yes | Energy Star Certified: No

What We Like
  • Portable

  • High cooling capacity

  • Digital controls

  • Remote included

What We Don't Like
  • Large unit

With a variety of modes and features, the 12,000 BTU portable air conditioner from SereneLife can cool, warm, and dehumidify. This unit is fairly large and takes up space, but you can mount it in a window if you plan to use it in the same room for a while. It’s still easy to move from room to room using the rolling wheelbase. It has three fan speeds, a digital touch control panel, and remote control, making it easy to get your room exactly how you want it.

Best for Large Rooms: Whynter ARC-14SH

Whynter ARC-14S

Cooling Area: 500 square feet | BTU: 14,000 BTU | Noise Level: 56 dBA | Window Size: Free-standing | Remote Control: Yes | Energy Star Certified: No

What We Like
  • Large cooling capacity

  • Eco-friendly refrigerant

  • Two filters

What We Don't Like
  • Large unit

This futuristic-looking air conditioning unit will keep large rooms (or small apartments) cool and comfortable with its 14,000 BTU rating. It is a free-standing unit but you can connect the exhaust hose to a window to allow any accumulated moisture to drain. It uses a CFC-free refrigerant, R32, which is better for the environment while still cooling efficiently. It also has two filters and can act as a dehumidifier. This unit does take up a lot of space and even if you use the window exhaust hose, you still need to have the unit itself positioned in your room.

Best for Small Rooms: BLACK+DECKER BPACT10WT Portable Air Conditioner

BLACK+DECKER BPACT10WT Portable Air Conditioner

Cooling Area: 150 square feet | BTU: 5,500 BTU | Noise Level: 75 dBA | Window Size: Free-standing | Remote Control: Yes | Energy Star Certified: No

What We Like
  • Portable

  • Easy installation

  • Multiple settings

  • Remote control

What We Don't Like
  • Free-standing

Small rooms can benefit from some serious cooling power with this free-standing unit from BLACK + DECKER. It wheels from room to room and uses an exhaust hose to drain through any window (setup kit included). You can use the remote control to choose between cool, fan, and dehumidify modes or set the temperature. You can also change the settings on the digital touch display on the top of the unit itself. While it does take up more floor space than an installed window unit, the modern, sleek design won’t be an eyesore in your home. It also includes a sleep mode, which lowers the noise level, making this a great choice for a bedroom.

Best Smart: Windmill 8,300 BTU 115-Volt Quiet/ECO/Smart Window Air Conditioner

8,300 BTU 115-Volt Quiet/ECO/Smart Window Air Conditioner

Cooling Area: 350 square feet | BTU: 8,300 BTU | Noise Level: 50 dBA | Window Size: 27-37 inches | Remote Control: Yes | Energy Star Certified: No

What We `Like
  • Great cooling efficiency

  • Modern design

  • Eco-friendly

  • Smart Home compatible

What We Don't Like
  • Expensive

Looking more like a smart phone design than an air conditioner, this window unit from Windmill is as modern-looking as it is efficient at cooling your room. It can cool rooms up to 350 square feet, which is pretty impressive for its compact size. It has three cooling and fan settings, which can be controlled from the unit itself, with the included remote, or using a voice command or app through your smart home device. 

Eco-conscious consumers will like that the company uses eco-friendly R32 refrigerant and offsets the carbon footprint of each unit purchased. This air conditioner is on the expensive side but will still fit in a lot of budgets. If you want the best in style and accessibility, this air conditioner from Windmill is the design of the future.

What Editors Say

"I love my Windmill AC! It cools down my apartment quickly and is super quiet, plus just looks nice and unobtrusive. Controlling it from the app is a game changer, especially on hot days when I want to return to a cool apartment without leaving the AC on while I'm out." — Nicole Lund, Commerce Editor

Best Quiet: Midea U Inverter Window Air Conditioner

Midea 8,000 BTU Smart Inverter U-Shaped Window Air Conditioner

Cooling Area: 350 square feet | BTU: 8,000 BTU | Noise Level: 42 dBA | Window Size: 22-36 inches | Remote Control: Yes | Energy Star Certified: Yes

What We Like
  • Extra quiet

  • Windows can open

  • Wifi compatible

What We Don't Like
  • Expensive

The U-shaped design of this window unit from Midea keeps the noise level of this air conditioner up to 9 times quieter than other models. In the lowest setting, the noise level is 42 dBA, the quietest that I’ve found available on the market. It allows your window to continue to open, even when installed. This is ideal for climates and seasons when you only need to run your air conditioner periodically but still want the benefits of fresh air when it is not in use. With an Energy Star Most Efficient 2020 certification, it can result in 35% less energy use than other models. This is a pricier unit but has so many great features that the slightly higher cost may be worth it to many consumers.

Final Verdict

Our top pick for a great air conditioning unit is the LG Energy Star Rated 6,000 BTU Window Air Conditioner (available at Walmart). This unit cools efficiently, has an included remote control and adjustable louvers that make operation a breeze. If you’re willing to spend more on a high-end air conditioning unit, the Windmill 8,300 BTU 115-Volt Quiet/ECO/Smart Window Air Conditioner (available at P.C. Richard & Son) has a modern design and smart home compatibility that will make it a seamless part of your home’s decor and setup.

What to Look for in an Air Conditioner


One of the first things you’ll want to consider is the style of air conditioner that works best for you. There are several options available, and they vary widely in terms of cost, capability, and installation requirements.

Two of the most common options for occasional users are portable and window air conditioners. Both of these options are fairly inexpensive and can be easily installed without professional help. However, the downside of these options is that they’re typically only powerful enough to cool one room at a time, which means you’ll need multiple units if you want air conditioning throughout your home.

Another option is a through-the-wall or built-in air conditioner, which is a permanent style. These styles are installed into a “sleeve” in an exterior wall of your home—ideal if your room doesn’t have an acceptable window. However, as you may have guessed, this style of air conditioner requires a more complex initial installation, as you’ll need professional help to cut an appropriate-sized hole in the wall.

For more comprehensive air conditioning, you may want to consider a ductless mini-split system. This style of air conditioner has gained popularity lately, as it’s a good permanent alternative for homes without central HVAC. As its name implies, there are no ducts required, and these units are typically more powerful than window units. However, mini-split systems are also fairly expensive and complex to install.

Finally, there are central air systems, which require ductwork throughout your home. These are the most expensive and complicated to install and, as such, are typically most common on new construction.

Unit size

If you’re going with a window or wall unit, measure the height and width of the opening to ensure you pick a compatible unit. It’s also beneficial to consider the weight of the unit, as this will determine whether you’ll need help moving and installing it.

Room size and location

Next, you’ll want to consider where you plan to put the air conditioner and how much square footage it needs to cool. The amount of heat an air conditioner can remove from a room is measured in BTUs, or British Thermal Units—larger rooms require a unit with a higher BTU.

Here’s a general breakdown of the recommended room size and BTU:

  • 100-300 square feet: 5,000-7,000 BTU per hour
  • 300-450 square feet: 8,000-10,000 BTU
  • 450-550 square feet: 10,000-12,000 BTU
  • 550-700 square feet: 13,000-14,000 BTU
  • 700-1,000 square feet: 18,000 BTU
  • 1,000+ square feet: 20,000 BTU and up

You’ll also want to consider the location of the room as you decide what BTU is best. For instance, a room that has several large windows and gets direct sunlight for several hours a day will likely be hotter and therefore need a more powerful air conditioner. In this situation, experts recommend increasing the BTU by at least 10 percent. Similarly, if your air conditioner will be in the kitchen—and, as a result, will have to combat the heat from the stove—you’ll want to bump up the capacity by about 4,000 BTU.

Noise level

If you plan to use your air conditioner in your bedroom or living room, you may be concerned with how much noise it produces. The noise level of appliances is typically measured in decibels, but since we don’t use this measurement in our daily lives, most people don’t know what “40 decibels” sound like. This can make it tricky to pick the best option for your needs.

In general, a standard air conditioner operates between 40 and 60 decibels. For reference, TVs usually operate at around 70 decibels, and normal talking falls between 40 and 60 decibels. So if you buy an air conditioner that operates at 60 decibels, it may interfere with your conversations or TV show. The quietest air conditioners out there operate at around 35 to 40 decibels, and their noise level is compared to that of a desk fan.

  • How do air conditioners work?

    All types of air conditioners work in pretty much the same way. First, they extract air and filter out any dust or impurities. That air is then passed over the cooling or evaporating coil, and the coil absorbs the heat. At the same time, during this step, moisture from the air is reduced to dew on the surface of the coil, effectively decreasing the humidity level in the room. Finally, the air is pushed back out of the device, lowering the room's overall temperature.

  • What types of air conditioners are there?

    There are several different types of air conditioners. Window units tend to be the most popular because they're affordable and easy to install, though some homes and apartments with unusually shaped windows may not accommodate them. Portable units are a great pick because they can be moved from room to room, but they also require more maintenance and aren't as efficient. Built-in or split systems offer a more permanent solution but require professional installation and can be costly.

  • How do you clean a window air conditioner?

    Check the filter of your window air conditioner each month, and clean it as needed. Also, take a look at the water pan inside the unit, and wipe it with a rag or sponge—this will help ensure proper drainage of the condensate created by the unit. It also helps prevent mold growth.

  • How do you install a window air conditioner?

    If you have basic DIY skills and some tools you most likely can install a window air conditioner yourself—although, because some units are very heavy and cumbersome, you might want to enlist a friend to help you. For those who aren't confident about installing an air conditioner themselves, you can ask the retailer when you're purchasing a new one, or try a service like HomeAdvisor.

  • How much does an air conditioner cost?

    The cost of an air conditioner varies by type and functionality—you can spend anywhere from $100 to several thousand dollars. Window models start at around $100 but can cost upward of $1,000 if you need one with advanced features and a high BTU capacity. Portable air conditioners tend to be slightly more expensive, typically costing between $200 and $500. Wall air conditioners generally cost $400 or more, and mini-split options start at around $800—plus the cost of installation. Central air systems are often desirable because they can be used for heating, as well, but you’ll likely pay several thousand dollars for the system and installation.

  • What are BTUs and why do they matter?

    The amount of heat an air conditioner can remove from a room is measured in BTUs, or British Thermal Units—larger rooms require a unit with a higher BTU. Energy Star recommends units around 6,000 BTU for rooms up to 250 square feet; 8,000 BTU units up to 350 square feet; 10,000 BTU units up to 450 square feet; and 12,000 BTU units up to 550 square feet.

Why Trust The Spruce?

This article was researched and written by Katie Begley, a writer specializing in home and garden products. While living in Hawaii, Katie came to know and love her home’s air conditioner window unit.

Article Sources
The Spruce uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Room Air Conditioners. United States Department of Energy and United States Environmental Protection Agency.