8 Best Window AC Units, According to Testing

Those of us without central air know just how hot and sticky summer temperatures can feel. Avoid spending your days sweating it out thanks to these top-performing window air conditioners from the most reliable brands, hand-picked by our pros at the Good Housekeeping Institute and grouped by room size, from 150 square feet to 450 square feet. While you're shopping for the best window AC, keep these four questions top of mind:

Is a window air conditioner or a portable AC unit better?

Window air conditioner units are the ideal pick for most rooms if you are able to physically install them on your windows. Unlike portable units, they won't take up space on the floor or require you to vent a long hose from the device to the outdoors. They tend to be quieter and cost less money for comparable capacity units. If you're unable to install a window unit or would prefer a portable one, check out our picks for the best portable air conditioners.

How do I find the right size air conditioning unit?

It's important to purchase the right size unit for your space, since getting too high of a capacity can mean you'll end up with excessive electricity bills on your hands. Meanwhile, a unit that is under-capacity will be inefficient. Most models list their cooling capacity on the box or website. This is a measurement in BTUs (British Thermal Units) that corresponds to the square footage of a room. Room units range from 4,000 to 20,000 or more, and in general,the larger the room, the more BTUs you will need.

While you can choose according to the square footage of the room you want to cool, you should be mindful of things that may make you want to size up, such as high ceilings, location (e.g., you'll want to size up in the kitchen where it can get warmer), and how sunny the room gets. It's also important to measure the height and width of the window opening to ensure that the unit can properly be mounted inside it.

Are window AC units energy efficient?

If you're all about energy savings, you can check an air conditioner's energy efficiency by looking at the EER rating (energy efficiency rating). It is derived by taking the BTU measurement and dividing that by the power consumption in watt-hours. The higher the efficiency rating, the less you’ll spend on home electricity bills.

You can also opt for a device with an energy-saver switch, which will ensure that the fans don’t operate continuously. Likewise, some have sleep modes that will raise the room temperature at night, which is more efficient (and means you won’t be freeze while you sleep).

What other air conditioner features should I consider?

• A “check filter” indicator visually reminds you that you have to clean or change out the filter.
• Oscillating ventshelp move the unit's air flow from side to side for more efficient room cooling.
• Remotes are great for adjusting the temp without having to move.
• "Smart" air conditioners allow you to operate the unit from your phone.

And now for the most important question: What are the best window air conditioners to keep you cool this summer?Overall, our top window AC unit recommendations for 2020 are: