Best small air conditioner

Heating, Cooling & Air Quality

Small air conditioners allow you to cool only the rooms you are actually occupying, which makes them a more economical choice than central AC units.

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Which small air conditioners are best?

Few inventions have made a larger difference in indoor comfort than air conditioners. No matter what the weather is like outside, you can be cool and comfortable in your home if it is equipped with an air conditioner. That said, there is no question that cooling a whole house uses a great deal of energy, which can create costly utility bills.

Small air conditioners solve this problem by enabling you to only cool the room you are currently occupying. This makes them a much more energy efficient option, without you having to sacrifice on comfort. 

There are several types of small air conditioners to choose from, but mini splits like the Bosch Ultra-Quiet 12K BTU are the most comparable to central AC units because they are designed for permanent installation and feature both an indoor and outdoor component.

What to know before you buy a small air conditioner

Types of small air conditioners

There are several types of air conditioners that can be classified as small air conditioners, each of which offers its own set of pros and cons.

Mini split air conditioner

Mini split air conditioners are common overseas in Europe and Asia, but less so in America. Like central AC units, mini splits have separate interior and exterior components, which means installation often requires the service of a professional. Most are designed to cool a single room, though there are also some models capable of zone cooling that feature a single exterior unit and several interior units. Many people find mini splits to be more aesthetically pleasing than window units and portable air conditioners, and they tend to be quieter too.

Window air conditioner

Window air conditioners are a more affordable option than mini splits and easier to install. In fact, many DIYers will have no trouble handling the installation themselves. Like mini splits, window units are also designed to cool a single room, but they are often louder and may have less features. Both mini splits and window air conditioners are considered more efficient than central AC units because you won’t waste energy cooling rooms you aren’t currently occupying.

Portable air conditioner

Portable air conditioners have a very simple installation process that only entails placing them in whichever room you want to cool, plugging them in and venting the hot air outside via a tube. This makes them an ideal option for those who don’t want to spend the money on separate air conditioners for every room, nor install a central AC unit. They also tend to be reasonably priced, making them good for those on a tight budget. The downside is that they take up floor space and are often even louder than window units.

Features to look for in a quality small air conditioner

Cooling capacity

The cooling capacity of air conditioners is measured in BTUs, and the more BTUs, the more powerful a particular air conditioner is. To determine how many BTUs you need, you should consider the square footage you want to cool, how many people normally occupy the space and how hot of a climate you live in. A good rule of thumb is to aim for between 30 and 40 BTUs per square foot, and increase that based on the other two factors. 

For example, if you want to cool a 200-square-foot room that rarely has more than two people inside and you live in a mild climate, a 6,000-BTU air conditioner should suffice. However, to cool that same size room, but one that is often occupied by four people and is located in a hot, tropical climate, you may want to opt for an 8,000-BTU unit.

Fan speeds

Most small air conditioners have several fan speed settings. The higher the setting, the more air it will move and the quicker it will cool down a room. However, higher settings are also noisier, which can be annoying if watching a movie or trying to sleep. 


These days, the majority of new window and portable air conditioners have a digital display that tells you the current fan speed and temperature setting. Mini splits may or may not have a display, and if they do, it generally only tells you the current temperature setting. The rest of the cooling and setting information will be viewable on the included remote control. If installing a small air conditioner in a bedroom, you may want to look for a model that allows you to dim or completely turn off the display so it doesn’t disturb you at night.

Adjustable vents

Adjustable vents allow you to direct the airflow to wherever you feel it is most needed. Depending on the model, you may have to manually adjust the vents by hand, or you may be able to do it via the remote control. Some models also had an oscillating mode that will continuously move the air flow up-and-down, side-to-side or both simultaneously.


Timers are helpful for programming cooling times based on your needs. For example, you may be able to program your air conditioner to start cooling the room 15 minutes before you normally arrive home after work or to stop cooling in the middle of the night when the ambient temperatures have dropped enough that you no longer need to waste energy on the air conditioner.


When purchasing a portable air conditioner, pay attention to the type of drainage system it has. Self-evaporative models don’t require draining or emptying, since the condensation automatically evaporates. Gravity-drain models have a hose that needs to be connected to a floor or sink drain, or anywhere else where water can run out without causing damage. Some models simply have a collection bin that you’ll regularly need to empty out, much like most portable dehumidifiers.

How much can you expect to spend on a small air conditioner

Mini air conditioners vary greatly in price by both type and cooling capacity. Both window and portable air conditioners cost between $100-$800. Mini split air conditioners cost between $700-$3,500.

Small air conditioner FAQ

Can I use an extension cord with my small air conditioner?

A. No. Most manufacturers recommend that you plug their portable and window air conditioners directly into a wall outlet. Mini splits require hardwiring.

How often do I need to clean or change the filter in my small air conditioner?

A. Just like with central AC units, it is recommended that you change or clean the filter on small air conditioners once a month. That said, some filters are specifically designed to last longer before they need to be cleaned or replaced, in which case that will be specified in its product details.

What are the best small air conditioners to buy?

Top small air conditioner

Bosch Ultra-Quiet 12K BTU 230V Mini Split Air Conditioner

Bosch Ultra-Quiet 12K BTU 230V Mini Split Air Conditioner

What you need to know: With a modern aesthetic and 12k-BTU rating, this mini split can effectively cool rooms up 400 square feet in the hottest of climates, and look good while doing so.

What you’ll love: It is capable of both heating and cooling and is Energy Star certified for efficient operation.

What you should consider: Installation requires the services of a professional.

Where to buy: Sold by Amazon

Top small air conditioner for the money

LG 6,000 BTU 115V Window Air Conditioner

LG 6,000 BTU 115V Window Air Conditioner

What you need to know: This affordably-priced option gets the job done in rooms up to 250 square feet and offers use-friendly installation and operation.

What you’ll love: It features a timer so you can start cooling a room before you get home, and there is an auto-restart feature that ensures you won’t wake up sweating if there is a short blackout in the middle of the night.

What you should consider: It is notably loud, even in the low-noise mode.

Where to buy: Sold by Amazon

Worth checking out

Whynter ARC-14SH

Whynter ARC-14SH

What you need to know: Surprisingly powerful for a portable unit, the Whynter ARC-14SH can cool as effectively as a mini split but doesn’t require the complicated installation.

What you’ll love: It has an activated carbon filter to remove odors from the air, and it has a wide thermostat range to help you achieve the ideal temperature.

What you should consider: It is expensive for a portable air conditioner.

Where to buy: Sold by Amazon


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 Brett Dvoretz writes for BestReviews. BestReviews has helped millions of consumers simplify their purchasing decisions, saving them time and money.

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