What is the smallest window air conditioner you can buy

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Small window AC units are ideal for renters with compact rooms. They allow you to cool off without making a major investment in your living space.

Below, we’re sharing our top picks for small window ACs. Whether value or energy efficiency is your priority, we’ve got the ideal unit for you.

Note: These small window ACs are for traditional double-hung windows that slide up and down. If you have casement windows or left-to-right sliding windows, check out our article on the best casement window air conditioners. 

Best small window ACs

Best overall

Midea Easy Cool

• Cools fast
• Reusable air filter

Best value

Frigidaire FFRA

• Lightweight
• Extra-long cord

Best over-the-sill

Soleus Air Exclusive

• Space-saving
• Controlled via app

Best for a studio apartment

Midea U Inverter

• Extremely energy-efficient
• Responds to voice commands

Top seller

LG window-mounted AC

• Fits the smallest windows
• Lots of feature options

What size window air conditioner do I need?

Before you start shopping for a small window AC, you need to know what size AC you’ll need. 

Physical size

First, check the size of your window. Measure the width and height of the opening within the window frame. Don’t purchase a unit that exceeds these dimensions. Most ACs list the maximum window size on the box.

It doesn’t matter if the unit is smaller than the width of your window. Most window air conditioners come with kits to seal off the extra space. 

Cooling capacity

British Thermal Units (BTU) is the measure for air conditioner capacity. The Environmental Protection Agency recommends at least 20 BTU for every one square foot of living space. 

To determine the BTU you’ll need to cool your space, multiply your square footage by 20. For example, if your room is 150 square feet, you need a small window AC unit with at least 3,000 BTU.

Electrical voltage

Ensure the small window AC unit you choose runs on standard residential circuits (between 115 and 125 volts). Most ACs with cooling capacities of 15,000 BTUs and below will operate on a standard circuit. But if you need a more powerful system, check the voltage requirements.

The best small window ACs

Check out our top picks for small window ACs below. We’ve included specifications for the lowest BTU model version of each.

SEER stands for Seasonal Energy Efficiency Rating. The higher the SEER, the more energy-efficient the air conditioner. Decibels refers to the noise level. The higher the number, the louder the unit.

Best overall small window AC

The Midea Easy Cool fits in windows 23-36 inches wide and at least 13 inches high. It has adjustable accordion panels on both sides to seal extra space. 

Installation is simple. The unit comes with all the equipment you need for mounting, except a screwdriver. (If you don’t already have one, we recommend this set.)

We like the Midea Easy Cool because it’s affordable (under $200 for lower BTU models) and effective. The controls are simple to understand, and the system operates fairly quietly.

With a reusable, easy to clean filter, you’ll save money and keep disposable filters out of the landfill. Plus, you’ll improve the air quality of your room.

The Midea Easy Cool is available on Amazon in 5,000-, 6,000-, 8,000-, 10,000-, and 12,000-BTU models.

Buy on Amazon

Best value small window AC

The Frigidaire FFRA is the least expensive of our small window AC picks. It provides solid efficiency at an affordable price point. 

We appreciate the Frigidaire FFRA’s extra-long electrical cord and straightforward control panel.

This air conditioner is intended for windows 23-36 inches wide and at least 13.25 inches high. It comes with a mounting kit and adjustable side panels to seal extra window space.

The Frigidaire FFRA is the most lightweight of the ACs we reviewed, at just 35 lbs. That’s less than half the weight of some of the other window ACs on our list. If you’re concerned about heavy lifting, this is the AC for you.

This Frigidaire window AC is available on Amazon in 5,000-, 6,000-, 8,000-, 10,000-, 12,000-, and 15,100-BTU models.

Buy on Amazon

Best over-the-sill small window AC

The Soleus Air Exclusive fits over your window sill. So, unlike the other models on our list, it doesn’t block your view. And it allows you to continue to open and close your window if and when you need to. 

Since the compressor piece of this AC sits outdoors, it’s whisper quiet. Plus, it’s simple to install right out of the box, requiring no tools or mounting equipment. However, it weighs 80 lbs., so you may need a friend to help lift it into place.

The Soleus Air Exclusive has many premium features like an automatic temperature sensor and voice control via Alexa and Google Assistant. You can control this small window AC from your phone using the SoleusAir app. These conveniences come at a cost – the Soleus Air Exclusive is more than double the price of some of the other picks on our list.

The one bummer about this unit is that you have to empty its water reservoir regularly to keep it running.

The Soleus Air Exclusive fits windows 24-48 inches wide. It will mount on window sills up to 11 inches wide. Though it doesn’t sit in the window, it requires an opening of at least 16 inches tall for installation.

It comes in 6,000- and 8,000-BTU models.

Buy on Amazon

Best small window AC for a studio apartment

The Midea U Inverter air conditioner is ultra-quiet because, like the Soleus Air Exclusive, the condenser portion of the unit sits outside the window. However, this U-shaped model mounts within the window rather than on the sill. Its unique form allows you to continue to open and close your window as needed. 

This small window AC is the most powerful of those we reviewed, making it ideal for open concept spaces like a studio apartment. It’s also the most energy-efficient. In fact, it won the Energy Star “Most Efficient” certification in 2022.

You can control this Midea AC from your phone using the MideaAir app. It’s also compatible with Alexa and Google Assistant for voice commands.

The Midea U Inverter fits windows 22-36 inches wide and at least 13.75 high. It comes with a window bracket for mounting and remote control. You’ll need a screwdriver, level, and measuring tape to install it.

This small window AC comes in 8,000-, 10,000-, and 12,000-BTU models.

Buy on Amazon

Top-selling small window AC 

This LG window air conditioner is the top-selling small window AC on Amazon. It’s highly rated by customers and often goes on sale, making its low price even more attractive. 

This small window AC fits windows 21-25 inches wide. It requires a height clearance of 12 inches. It’s the smallest of all the small ACs on our list.

We like that LG offers a line with many options. For example, you can choose a less expensive unit with a knob to control the temperature if you just want something simple. Or you can pay a little bit more for digital controls.

We also appreciate that this AC comes with an installation kit that helps you lift this 40 lb. system into the window.

Amazon sells 5,000-, 6,000-, 8,000-, 10,000-, 12,000-, 18,000-, and 25,000-BTU models of this LG window AC.

Buy on Amazon

The advantages of a window air conditioner

Window air conditioners are ideal for renters because they can go with you when you move. Window AC installation is easy, and so is removal. 

Small window ACs are an inexpensive way to make your place more comfortable. And many are quite energy-efficient so they won’t boost your electric bill significantly.

Even though they’re affordable, they’re effective. Window ACs can quickly cool a room.

Plus, you don’t have to sacrifice your view with some of the ACs on our list. Over-the-sill and U-shaped models let you continue to open and close your window as needed.

If your place has small windows, you can still enjoy all the benefits of a window AC with one of the models on our top small window AC list!