On this page
- Compare at a glance
- The picks
- How we picked
- What ENERGY STAR means for a window AC
- Choosing the right BTU for your room
- Inverter vs fixed-speed compressors
- Noise levels and placement
- Key features to look for
- Questions people ask
This guide is based only on published specifications from manufacturers and ENERGY STAR program materials. We compared cooling capacity, room coverage, noise, wattage, weight, and listed features to rank each window unit.
Compare at a glance
Specs are the figures each maker lists. "Not listed" means we have no published figure yet.
The picks
No. 1Best for large rooms
LG Dual Inverter ThinQ 14,000 BTU Window
- Type
- Window
- Rated cooling
- 14,000 BTU
- Room size
- Up to 800 sq ft
- Rated noise
- Not listed
- ENERGY STAR
- Yes
This LG unit offers 14,000 BTU and the largest maker room figure in the group at 800 square feet, though the ENERGY STAR chart pairs 14,000 BTU with 550 to 700 square feet. Compared with the 12,000 BTU LG ThinQ Alexa below, it adds more cooling power. Its 44 db noise level matches the quieter 12,000 BTU pick.
Why it made the list
- 14,000 BTU cooling capacity
- Covers up to 800 sq ft
- 44 db noise level
- Inverter compressor and WiFi
Trade-offs
- Heavy at 85.1 pounds
- 1260 watts listed
Good fit if
- Large living rooms or open floor plans
- Spaces that need strong cooling on hot days
Skip if
- You have a small bedroom under 400 sq ft
- You want a lightweight unit that is easy to move
Bottom line: The strongest cooling pick for large spaces among ENERGY STAR window units.
Check price on AmazonNo. 2Best 12,000 BTU efficiency
LG ThinQ Alexa 12,000 BTU
- Type
- Window
- Rated cooling
- 12,000 BTU
- Room size
- Up to 550 sq ft
- Rated noise
- Not listed
- ENERGY STAR
- Yes
This LG model pairs 12,000 BTU with a 44 db noise level and covers 550 square feet. Compared with the Midea 12,000 BTU below, it does not state a heating function.
Why it made the list
- 12,000 BTU capacity
- 44 db noise level
- Inverter compressor
- WiFi enabled
Trade-offs
- No heating function stated
- No wattage listed
- Smaller coverage than the 14,000 BTU pick
Good fit if
- Medium rooms around 550 sq ft
- Buyers who prioritize quiet operation
Skip if
- You need supplemental heating
- You want the largest possible cooling capacity
Bottom line: A balanced 12,000 BTU pick with quiet operation and WiFi.
Check price on AmazonNo. 3Best for heating and cooling
Midea Air Conditioner Heat
- Type
- Window
- Rated cooling
- 12,000 BTU
- Room size
- Up to 550 sq ft
- Rated noise
- Not listed
- ENERGY STAR
- Yes
The Midea 12,000 BTU adds a heating function, making it the only pick here that can warm a room. It covers 550 square feet and includes a dehumidifier. Compared with the LG 12,000 BTU above, it adds a heating function but lists a higher noise level of 45 db.
Why it made the list
- Heating and cooling function
- 12,000 BTU capacity
- Covers up to 550 sq ft
- Dehumidifier included
Trade-offs
- 45 db noise level
- No inverter compressor stated
Good fit if
- Rooms that need supplemental heat in cooler months
- Medium spaces up to 550 sq ft
Skip if
- You want the quietest operation
- You prefer an inverter compressor
Bottom line: A versatile ENERGY STAR window unit with heating for year-round use.
Check price on AmazonNo. 4Quietest small-room pick
Midea Air Conditioner Rated Savings
- Type
- Window
- Rated cooling
- 7,800 BTU
- Room size
- Up to 340 sq ft
- Rated noise
- Not listed
- ENERGY STAR
- Yes
At 39 db, this Midea 7,800 BTU unit is the quietest option in the guide. It uses 605 watts and covers up to 340 square feet. Compared with the Frigidaire 8,000 BTU Inverter below, it is quieter but does not state an inverter compressor.
Why it made the list
- 39 db noise level
- 605 watts listed
- Dehumidifier included
- Covers up to 340 sq ft
Trade-offs
- Smaller coverage at 340 sq ft
- No inverter compressor stated
- No heating function stated
Good fit if
- Bedrooms or small offices
- Spaces where low noise is a priority
Skip if
- You need to cool a room larger than 340 sq ft
- You want an inverter compressor
Bottom line: The quietest ENERGY STAR window unit for small rooms.
Check price on AmazonNo. 5Best inverter small-room unit
Frigidaire BTU
- Type
- Window
- Rated cooling
- 8,000 BTU
- Room size
- Up to 350 sq ft
- Rated noise
- Not listed
- ENERGY STAR
- Yes
This Frigidaire 8,000 BTU Inverter has a 41 db noise level and covers 350 square feet. Compared with the Midea 7,800 BTU above, it is slightly louder but states an inverter compressor.
Why it made the list
- Inverter compressor
- 41 db noise level
- WiFi enabled
- Covers up to 350 sq ft
Trade-offs
- No dehumidifier listed
- No heating function stated
- 55 pounds
Good fit if
- Small rooms where an inverter is preferred
- Users who want app control
Skip if
- You want a listed dehumidifier
- You want the absolute lowest noise
Bottom line: A quiet inverter option for small spaces with WiFi.
Check price on AmazonNo. 6Best fast cooling small room
Midea 8,000 BTU Window
- Type
- Window
- Rated cooling
- 8,000 BTU
- Room size
- Up to 350 sq ft
- Rated noise
- Not listed
- ENERGY STAR
- Yes
The Midea 8,000 BTU Window has a Fast Cooling mode and covers 350 square feet. Compared with the Frigidaire 8,000 BTU Inverter above, it is louder but adds fast cooling and a dehumidifier.
Why it made the list
- Fast Cooling mode
- Dehumidifier included
- Covers up to 350 sq ft
- App control
Trade-offs
- 53.5 db noise level
- No inverter compressor stated
Good fit if
- Rooms where noise is less important
- Spaces that need quick cooling
Skip if
- You plan to use it in a bedroom
- You need quiet operation
Bottom line: A capable 8,000 BTU unit with fast cooling but noticeable noise.
Check price on AmazonHow we picked
We compared the published specifications for window air conditioners whose listings state ENERGY STAR certification. The ranking uses cooling capacity, room coverage in square feet, noise level, wattage, weight, and listed features such as inverter compressors, WiFi, dehumidifiers, and heating functions.
No unit was handled or measured for this guide. All data comes from manufacturer listings and ENERGY STAR program materials, and we did not use customer ratings or prices.
What ENERGY STAR means for a window AC
ENERGY STAR certified room air conditioners meet efficiency criteria set by the U.S. Environmental Protection Agency. According to the ENERGY STAR program, certified units use less energy than standard models and often include variable speed technology that saves energy and runs more quietly.
For more detail on the criteria and what the label covers, see our ENERGY STAR room AC criteria guide.
Choosing the right BTU for your room
Cooling capacity is stated in BTU, and each listing includes a recommended room size in square feet. The ENERGY STAR sizing guidance suggests matching capacity to floor area: for example, 300 to 350 square feet typically calls for 8,000 BTU, while 550 square feet calls for 12,000 BTU and 700 square feet calls for 14,000 BTU.
An oversized unit can cool the room before removing enough humidity, leaving the air feeling damp. Use our BTU and room size guide to match your space.
Inverter vs fixed-speed compressors
Several picks in this guide use an inverter compressor, which varies its speed to maintain temperature instead of cycling fully on and off. This can reduce energy use and noise compared with a fixed-speed compressor.
The ENERGY STAR program notes that variable speed technology allows a room air conditioner to quietly regulate temperature and save energy. See our inverter vs fixed-speed comparison for more.
Noise levels and placement
Noise levels in this guide range from 39 db to 53.5 db. For bedrooms, the quietest picks are the Midea 7,800 BTU at 39 db and the Frigidaire 8,000 BTU Inverter at 41 db.
ENERGY STAR notes that U-shaped and saddle-style units, which keep the compressor outside the room, give greater noise reduction. Our window AC noise guide explains what you hear indoors and outdoors.
Key features to look for
Beyond cooling, the picks here list features such as dehumidifiers, WiFi, filter reminders and, on one model, heating. Dehumidifiers help remove moisture on humid days, while WiFi allows scheduling and remote control through an app.
The Midea 12,000 BTU is the only pick in this guide that lists both heating and cooling. Check the window AC buying checklist for a full list of features to consider.
Related: Best Inverter Window Air Conditioner: Inverter AC Reviews · Best Dual Hose Portable Air Conditioner: Reviews by SACC
Questions people ask
What does ENERGY STAR mean for a window air conditioner?
ENERGY STAR certified room air conditioners meet efficiency criteria set by the U.S. Environmental Protection Agency. Certified units use less energy than standard models and often include variable speed technology for quieter, more efficient operation.
How do you know what size window AC you need?
Match the unit's BTU rating to your room's square footage. The ENERGY STAR sizing chart suggests 8,000 BTU for 300 to 350 square feet, 12,000 BTU for 450 to 550 square feet, and 14,000 BTU for 550 to 700 square feet. Adjust for sun exposure, ceiling height, and heat-producing appliances.
Are inverter window air conditioners quieter?
Inverter compressors vary their speed instead of cycling fully on and off, which can reduce noise and temperature swings. In this guide, the inverter picks have noise levels of 41 to 44 db, while the loudest pick, which does not state an inverter, lists 53.5 db.
Do all ENERGY STAR window ACs have WiFi?
No. WiFi is an optional feature. In this guide, the LG Dual Inverter ThinQ 14,000 BTU, LG ThinQ Alexa 12,000 BTU, and Frigidaire 8,000 BTU Inverter list WiFi; the Midea picks list app control without naming WiFi in their features.
Can a window AC with heating be used in winter?
Only if the unit lists a heating function. The Midea 12,000 BTU is the only pick in this guide that lists heating and cooling. Check the manufacturer's specifications before using a unit for heat.
How noisy are these window air conditioners?
Noise levels range from 39 db to 53.5 db. The Midea 7,800 BTU is the quietest at 39 db, while the Midea 8,000 BTU Window is the loudest at 53.5 db. For a bedroom, favor the lower figures.
Last updated November 6, 2026
