6 Best Portable Air Conditioners, After Testing 30+

Our home experts start by shopping the current marketplace to identify the top-selling portable ACs that you’re most likely to find at stores and online. Next, we identify brands that have performed the best and proven the most reliable through years of AC testing at the Institute. We also consider newer brands with unique features or innovations.

Hands-on evaluations mainly happened in our Home Improvement & Outdoor Lab, where our engineers and experts spent more than 100 hours testing and reviewing 30 new models and analyzing scores of technical data.

Performance testing covers multiple factors. We check to see how close the air temperature coming out of the AC is to our set point. Next, we measure air speed with an anemometer (pictured). This tells us how quickly the AC can cool a room.

Portable ACs require a single or dual hose for exhausting leftover heat through a vented window. The best choice for you will come down to a few factors.

✔️ Single-hose portable AC: This is the most common type of portable air conditioner and also the least expensive. So if you're on a tight budget, it's your best bet. It features one exhaust hose which vents heat from the unit to the outside. Air to be cooled is pulled directly from the room. This negative pressure in the room can pull hot air from outside which makes it harder for the AC to maintain consistent temperatures. For this reason, our experts say single-hose ACs are generally best for smaller spaces (200 square feet or less) where the heat and humidity aren't too extreme.

✔️ Dual-hose portable AC: These units feature two hoses that usually connect to the same window—one to take air in and one to exhaust it. Using outside air to cool the system instead of air from the room eliminates the negative pressure issue. That's why our experts say to go for a dual-hose unit if you need to cool a larger space that can get quite hot and humid. It will be more effective at keeping the room cool and it will use less energy in the process since the motor won't have to work as hard.

✔️ Evaporative coolers: These types of coolers are portable, but they do not have exhaust hoses. The only moving part is the internal fan that moves air across a water reservoir and cooling pads. ECs produce more of a cool breeze than a blast of cold air; they're ideal in dry climates where humidity levels are low and the air is hot. Since they don't need to be exhausted, you can use ECs in any space, or even outside.

BTUs are a measure of air conditioner capacity that equates to a particular room size. Choosing the right capacity is essential: Too strong and you’ll waste unnecessary power; too weak and it won't cool effectively and will waste energy by continuously running at full tilt. That's why the Department of Energy (DOE) recommends an average of 20 BTUs for each square foot of living space.

✔️ When to size down in BTUs: After you calculate BTUs based on room size, you might find that you're in between offered sizes. Our experts say it's better to opt for the smaller unit. Using too powerful of an AC can be detrimental to the cooling and the comfort of the room.

✔️ When to size up in BTUs: It's important to recognize that not all rooms are built the same. You’ll want to size up your AC if it is in a room with the following:

• High ceilings that create more space that needs to be cooled
• High traffic as more people means more heat generated
• Lots of sun (e.g. a room with a lot of south-facing windows)
• Near the kitchen with a lot of heat-generating appliances

Note: The industry uses two different BTU ratings: SACC and ASHRAE. Short for Seasonally Adjusted Cooling Capacity, SACC is a newer rating system that considers real-world conditions, like indoor temperature and humidity levels. ASHRAE, short for American Society of Heating, Refrigerating, and Air-Conditioning Engineers, is based on controlled lab conditions with consistent temperatures.

Short answer: no. Window ACs cool more effectively and efficiently than portable units, because their heat-generating mechanical parts are located outside of the room that's being cooled.

• Portable ACs are easier to move. They're on wheels after all. Window ACs need to be properly secured, held in place, and connected to the window.
• Portable ACs fit more window types. Another benefit of a portable AC's exhaust hose is that it allows the unit to connect to different window types. While window ACs only work with vertical double-hung windows, portable ACs work with horizontal sliding windows as well.
• Portable ACs are noisier and heavier than window ACs. Portable units tend to be louder, since all their mechanicals are sitting right there in the room, instead of out the window. They can also be larger than their counterparts, weighing up to 80 pounds.
• Portable ACs take up more square footage than window ACs. Because they sit inside the room they cool, portable ACs take up more floor space. Our experts recommend placing the unit away from walls so the airflow isn’t restricted, but that will likely mean a longer hose and more space taken up.

Standard portable ACs must be vented with a hose out a window to exhaust the hot air they produce. You can also choose to vent through a wall or ceiling—anything that will send the hot air to another space. The machines don't produce toxic fumes, like carbon monoxide, so the venting is about cooling performance, not safety.

However, evaporative coolers don't need to be vented. These units require a large amount of water or ice to cool the space.

The Good Housekeeping Institute provides expert reviews and advice on all things home-related, including portable air conditioners and other HVAC equipment. This project was spearheaded by Alec Scherma, test engineer at the Institute. Scherma's background in mechanical engineering and HVAC consulting provides testing expertise and knowledge on the different types of HVAC equipment one can purchase.

Scherma worked closely with Dan DiClerico, director of the Home Improvement & Outdoor Lab. DiClerico brings more than 25 years of experience to the Institute and has tested and reviewed thousands of home-comfort products, including air purifiers, space heaters and humidifiers.