Best Inverter Air Conditioners – 2021 Ultimate Guide

If you’re afraid that buying an air conditioner will cause a spike in your utility bill, then you should choose an inverter air conditioner. An inverter air conditioner will ensure that the air conditioner uses the compressor when necessary, rather than throughout the duration that the unit is being used.

To put it simply, the inverter will prevent the unit from using too much unnecessary energy, ultimately saving you money in the long run.

If you’re unsure of which inverter air conditioner is the best, don’t worry. We’ve got you covered in this ultimate guide.

Comparison of the Best Inverter Air Conditioners

  • Easily save more than 35 percent on energy
  • With extreme quiet operation it runs very quiet at only 42dB
  • Very easy to install in the window space
View Latest Price ?
  • Up to 10 years limited warranty included
  • Quickly and easily cools down up to 9000 Btu
  • Remote control included for much easier operation
View Latest Price ?
  • Best for the Money
  • Strong and lightweight construction for durability
  • 9000 Btu maximum cooling capacity
View Latest Price ?
  • Quickly and easily cools down up to 12000 Btu
  • Remote control included for much easier operation
  • Save more than 35 percent on energy
View Latest Price ?
  • Makes use of automatic airswing for better distribution
  • 12000 Btu maximum cooling capacity
  • Very fast cooling option in only a few minutes
View Latest Price ?

How Do I Choose an Energy Efficient Inverter Air Conditioner?

To choose an energy-efficient inverter air conditioner, you will need to take into consideration the size of your room, the BTU of the unit, and the Energy Star certification, if applicable.

Calculate Your Room Size

The square footage of the room determines the area that an air conditioner will cover. To calculate your room’s area, you will multiply the room's width by the length of the room in feet. This will give you the total area of the room in square feet.

For example, if you have a 20 feet long room by 30 feet wide, you will multiply 20 x 30 to get 600 square feet. This means you will need an energy-efficient inverter air conditioner that will cool a room up to 600 square feet.

Midea U Inverter MAW10V1QWT

BTU of the Unit

Air conditioning units are determined by BTU. BTU stands for British thermal unit, and it is the calculation of a 1°F temperature change in one pound of water.

Using the same example above, if you have a 600 square foot room, you will need an air conditioner with a sufficient BTU output.

Generally, a 600 square foot room can use an air conditioner that has around 14,000 BTU.

Energy Star Certification

Energy Star is a program designed by the U.S. Environmental Protection Agency (EPA) and the U.S. Department of Energy to promote the use of energy-efficient appliances. Appliances certified as energy-efficient will have an Energy Star rating assigned by the EPA and Department of Energy.

The Energy Star rating is also commonly referred to as an EER (energy efficiency ratio). Generally, any appliance with an EER of 8 or better is considered energy-efficient, with the higher EER meaning better energy efficiency.

Review of the Best Inverter Air Conditioners

We have included a list of the 5 best inverter air conditioners for each category you may need. Each product has informative pros and cons, along with a brief description of what recent buyers are currently saying about the product.

Best Overall:
Midea U Inverter MAW10V1QWT

Midea 10,000 BTU U-Shaped Smart Inverter Window Air Conditioner–Cools up to 450 Sq. Ft., Ultra Quiet with Open Window Flexibility, Works with Alexa/Google Assistant, 35% Energy Savings, Remote Control


  • Saves up to 35% in energy savings per year
  • Extremely quiet; 9x quieter than comparable units
  • 10,000 BTU makes it ideal for cooling a room up to 450 square feet
  • First window unit to receive the Energy Star Most Efficient 2020 Certification
  • Wi-Fi technology is built into the unit, allowing it to be controlled from a Smartphone application, Amazon Alexa, or Google Assistant


  • Installation can be somewhat difficult
  • Will not drain properly if not installed with a slight tilt

What Recent Buyers Report

Recent buyers all agree that the amount of energy that is saved with this unit is substantial. In addition to energy savings, users are also most pleased with how quiet this unit is compared to the rest. These are the two main features that make recent buyers the happiest.

Why it Stands Out to Us

The Midea U Inverter MAW10V1QWT is our choice for the best overall inverter air conditioner because it is extremely energy efficient, has a high BTU output for cooling rooms up to approximately 450 square feet, and is extremely quiet. These three features set this unit apart from the competition.

We also like that the unit can be controlled through a Smartphone application, as well as Google Assistant or Amazon Alexa. This makes adjusting the temperature, settings, and mode of the unit quick and easy.

Bottom Line

For an energy-efficient inverter air conditioner that won’t break the bank and will save you money in the long run, we recommend the Midea U Inverter MAW10V1QWT. It is easy to use and extremely effective once installed.

Daikin 9000 BTU 17 SEER

No products found.


  • Comes with a 10-year warranty
  • Seasonal energy efficiency ratio of 17
  • Low noise production (37 decibels indoors)
  • Easy to use with a variety of functions, modes, and settings to choose from
  • POWERFUL operation boost button gives you an additional 20-minute boost of cooling


  • Slightly pricier than some comparable models
  • Can be difficult to install for the average DIY-er

What Recent Buyers Report

This unit by Daikin is a user favorite because it is energy-efficient and exceptionally quiet. It also gives users the option to run a 20-minute cooling boost using the POWERFUL button on the remote.

Why it Stands Out to Us

The Daikin 9000 BTU 17 SEER first stands out to us because it has an energy efficiency ratio of 17. This makes it one of the most energy-efficient models on the market.

We also like that Daikin includes a 10-year warranty with the unit. The unit is generally easy to use once installed but may require professional installation if you are unfamiliar with installing air conditioner units.

Bottom Line

The Daikin 9000 BTU is perfect for cooling rooms up to 400 square feet. The quiet technology makes it especially ideal for bedrooms or other areas that require as little noise as possible.

Best for the Money:
Klimaire KSIV009-H119-S(W)

Klimaire 9,000 BTU 21.5 SEER2 Ductless Mini-Split Inverter Air Conditioner Heat Pump System with All-Inclusive 16' Installation Kit and Wall Bracket (115V)


  • Extremely quiet at only 25 dB
  • Highly energy efficient with a SEER of 19
  • 5-year manufacturer compressor warranty
  • 9,000 BTU cools an area up to 350 square feet
  • A variety of settings and functions including a self-cleaning function, sleep mode, auto-restart, follow me, and a programmable timer


  • Relatively heavy unit weighing 75 pounds
  • Can be difficult to install if unfamiliar with HVAC

What Recent Buyers Report

Recent buyers have been the most pleased with how much cold air this unit produces while using so little energy. Users agree it is the best inverter air conditioner for the money, especially when needing to cool rooms that are 350 square feet or less.

Why it Stands Out to Us

The Klimaire KSIV0009-H119-S(W) is one of the quietest inverter air conditioners available today, which is one of the main features that sets this unit apart from the rest. Additionally, the sleep mode, auto-cleaning feature, and programmable timer also make this unit the best for the money.

In addition to the features you receive for the cost of the unit, we also believe that the Klimaire 5-year compressor warranty is the final feature that causes this unit to stand out from the rest.

Bottom Line

The Klimaire KSIV0009-H119-S(W) is the best inverter air conditioner for the money because of the variety of features you get with such an energy-efficient unit.

Editor's Pick:

Pioneer Air Conditioner WYS012A-20 Wall Mount Ductless Inverter+ Mini Split Heat Pump, 12000 BTU-110/120V


  • Extremely energy efficient with a SEER of 19
  • 5-year parts and 5-year compressor warranty
  • Large BTU output will cool an area up to 500 square feet
  • Ultra-silent technology makes it an exceptionally quiet unit
  • Remote control included with backlit LED screen and easy to use functions


  • Can be difficult to install for one person
  • Installation instructions are difficult to understand

What Recent Buyers Report

While recent buyers agree that installation can be difficult for the average DIY-er, the unit makes up for this in energy-efficiency and quiet technology. The remote control with the backlit LED screen also makes it easy to control at night.

Why it Stands Out to Us

This is the Editor’s Pick because it is extremely energy-efficient, quiet, and powerful. It can cool a room up to 500 square feet in a short amount of time, all while saving energy by doing so. It also comes with a 5-year part and 5-year compressor warranty, which helps you rest assured that you won’t be out of an air conditioning unit for long if something goes wrong.

Bottom Line

For the price and the features you receive with this unit, the Pioneer WYS012A-19 is hard to beat. It will cool an area up to 500 square feet while maintaining optimal energy efficiency with an overall quiet sound.

Honorable Mention:
Classic America MSC-12-HAC1

Classic America (12000BTU/120VAC/20SEER) Mini Split AC/Heating System - 600 SqFt Coverage - Ductless/Wall Mounted - Energy Saving Inverter - Includes 16' Installation Kit and Remote - WiFi/Alexa Ready


  • Washable air filter for easy cleaning
  • Exceptional seasonal energy efficiency ratio of 20
  • The turbo button can be pushed to provide an extra boost of cooling power
  • 1-year manufacturer’s warranty on the unit as long as the unit is properly installed
  • Easy to use with a variety of modes, settings, and functions to choose the exact cooling setting you need


  • Can leak if copper tubing is not installed properly
  • Warranty is voided if the unit has not been properly installed

What Recent Buyers Report

Recent buyers are most pleased with the unit's exceptional energy efficiency that is combined with the many different features, settings, and modes you can choose between when using the unit.

Why it Stands Out to Us

The Classic America MSC-12-HAC1 stands out to us because it is one of the most energy-efficient models available on the market today. The washable air filter is also a feature that we feel is worth mentioning because it prevents you from purchasing replacement air filters for the unit. Simply remove the air filter from the unit, rinse it with water, dry it completely, and then place it back into the unit.

Bottom Line

We made sure the Classic America MSC-12-HAC1 was our choice for honorable mention because it is affordable, energy-efficient, and loaded with various features. This makes it one of the best inverter air conditioners on the market today.

What is an Inverter Air Conditioner?

An inverter air conditioner is a traditional air conditioner that contains an inverter. The inverter is what makes the air conditioner energy efficient.

Inverter air conditioners are best used to maintain a climate that can fluctuate periodically throughout the day, such as a home or office. The inverter will ultimately tell the unit when to run and when to stop, making it energy efficient.

How Does an Inverter Air Conditioner Work? 

The inverter works by telling the compressor in the unit when to run and for how long to run so that it can achieve the target temperature that has been set. When the temperature has been reached, the inverter will tell the unit to stop cooling (but will likely keep the fan on to circulate air). 

With a traditional air conditioner, the unit would continue to run even after the target temperature has been reached, ultimately using a large amount of energy to do so.

Comparison Overview

Inverter Air Conditioner vs Non-Inverter

An inverter air conditioner will regulate the compressor's speed and frequency to cool a room according to the temperature that has been set. Once the temperature has been reached, the inverter will stop or slow the compressor to save energy.

A non-inverter air conditioner will only function in stop or go mode, meaning, it’s either on or off. There is no regulation of the compressor with a non-inverter air conditioner. When it’s on, it’s on, and it can only be stopped by telling it to stop. This is how non-inverter air conditioners use so much energy.

Klimaire KSIV009-H119-S(W)

Advantages and Disadvantages of an Inverter Air Conditioner


Energy Efficient

The biggest advantage of an inverter air conditioner is energy efficiency. This means saving money on your overall monthly utility bill because the unit is only running when it needs to versus running 24/7.

Quieter than Non-Inverter Units

An inverter air conditioner will slow down or stop when it doesn’t need to cool, which typically lowers the overall noise that is produced from the unit, especially when comparing it to a non-inverter unit.

More Variety of Modes and Function

Non-inverter air conditioners are very basic, with only the ability to control the fan speed and if you want to cool or not. Inverter air conditioners have a larger variety of modes, settings, and functions because they can perform more functions, such as turbo cold and sleep timers.



Inverter air conditioners are typically always more expensive than non-inverter air conditioners. This means you likely have to bite the bullet in the upfront costs, but you will save money on your utility bill in the long run because of the amount of energy saved when using the unit.


If you have the opportunity to purchase an inverter air conditioner, we highly recommend it. They are energy-efficient, extremely functional, and can cool areas both big and small.

People Also Ask

Still, looking for the best inverter air conditioners for energy efficiency? There are several types of air conditioning systems available on the market today but how do these provide you with the energy efficiency you are looking for? Read on to find out more.

Does Inverter AC Really Save Electricity?

Yes, the inverter air conditioner saves electricity by preventing the compressor of the unit from constantly running. It will turn off or slow when it senses the temperature has been reached. This keeps the unit from overworking and burning extra energy, ultimately saving you money and electricity in the long run.

Is Inverter AC Good For Home?

We recommend using an inverter AC for your home, especially if you have a room in your home that always seems to stay hotter than most. This will prevent you from overusing your central air conditioning system, which will ultimately use more electricity in the home. An inverter AC will cool the room in your home to the exact temperature you need without being overworked.

Do I Need Stabilizer For Inverter AC?

You will only need a stabilizer for an inverter AC if there is no S-UTR compressor included with the unit. This is recommended to ensure the unit works properly for as long as possible.

How Much Electricity Does an Inverter AC Use?

An inverter AC saves electricity by reaching the target temperature more quickly and then adjusting the compressor accordingly.

An inverter AC can reach the desired temperature up to 25% quicker than a non-inverter AC. Once the temperature has been reached, the inverter AC uses 40% less power than a non-inverter AC.