8 Best Conventional Window Air Conditioners Under $400 in 2026
We compared eight conventional window air conditioners under $400, including inverter models, on room coverage, noise, efficiency and window fit.
By Daniel Brooks
Updated October 15, 2026
Conventional window air conditioners under $400 are where inverter compressors, ENERGY STAR certification and 10,000 to 12,000 BTU capacity become affordable. Our guide to the best conventional window air conditioners under $400 compares eight units, from a 40 dBA 8,000 BTU inverter for bedrooms to a 12,000 BTU inverter rated for 520 sq ft. For every size and type in this category, see our Conventional Window Air Conditioners page.
All eight were listed under the $400 cap when we checked prices in October 2026. Four of them use an inverter compressor, which varies its speed instead of cycling on and off, so they run quieter and hold a steadier temperature. The other four are standard units that give you more capacity or extra features for the money. We compared room coverage, compressor type, noise, controls, window fit and buyer feedback.
All Products Compared
| Product | Best For | Cooling Capacity | Room Size | Noise | Notable Feature |
|---|---|---|---|---|---|
| Midea 8,000 BTU Smart Inverter Window Air Conditioner | Overall | 8,000 BTU | Up to 350 sq ft | As low as 40 dBA | Inverter, ENERGY STAR certified |
| ROVSUN 12,000 BTU Inverter Window Air Conditioner | Large rooms | 12,000 BTU | Up to 520 sq ft | 42 dBA in sleep mode | Inverter with 4-way swing |
| Windmill 10,000 BTU WhisperTech Window Air Conditioner | Medium rooms | 10,000 BTU | 350 to 450 sq ft | 40 dB | Dual air intake, tool-free kit |
| Frigidaire 8,000 BTU Smart Inverter Window Air Conditioner | Alexa and Google Home | 8,000 BTU | Up to 350 sq ft | 41 dB | Inverter, ENERGY STAR certified |
| LG 10,000 BTU Window Air Conditioner (LW1024RSMX) | LG ThinQ users | 10,000 BTU | Up to 450 sq ft | 52 dB | ThinQ app control |
| Whirlpool 10,000 BTU Window Air Conditioner | Dehumidifying | 10,000 BTU | Up to 450 sq ft | 59 dB | ENERGY STAR rated, 12.1 EER |
| BLACK+DECKER 12,000 BTU Window Air Conditioner | Capacity per dollar | 12,000 BTU | Up to 550 sq ft | 59 dB | 5-year compressor parts coverage |
| Hisense 10,000 BTU Window Air Conditioner | App on a budget | 10,000 BTU | Up to 450 sq ft | 53 dB | ConnectLife app |
| Award | Product | WikiCooling Score About WikiCooling ScoreThe WikiCooling Score is our own rating from 0 to 10, based on the criteria described on our How We Review page. It reflects research, not laboratory measurement, and is never influenced by manufacturers, retailers, or affiliate commissions. Learn more › | |
|---|---|---|---|
| Best Value |
Midea 8,000 BTU Smart Inverter Window Air
|
8.1/10 | Buy |
ROVSUN 12000 BTU Inverter Window Air Conditioner
|
7.8/10 | Buy | |
Windmill 10,000 BTU WhisperTech Window Air
|
7.8/10 | Buy | |
| Best Budget |
Frigidaire 8,000 BTU Smart Inverter Window Air
|
8.0/10 | Buy |
LG LW1024RSMX 10,000 BTU Window Air Conditioner
|
8.0/10 | Buy | |
Whirlpool 10,000 BTU Window Air Conditioner
|
7.8/10 | Buy | |
| Best Premium |
BLACK+DECKER 12,000 BTU Window Air Conditioner
|
8.0/10 | Buy |
| Best Overall |
Hisense 10,000 BTU Window Air Conditioner
|
8.1/10 | Buy |
Midea 8,000 BTU Smart Inverter Window Air
This 8,000 BTU window air conditioner from Midea uses inverter technology for quiet, efficient cooling up to 350 square feet. It offers app, voice, and remote control, making it a strong choice for bedrooms or living spaces where low noise and smart features matter.
Pros
- Very quiet operation at 40 dB
- Smart app and voice control
- Energy-efficient inverter technology
- Cools up to 350 sq ft
- Easy installation with included bracket
Cons
- Heavy for one person to install (43 lbs)
- Fits only windows with minimum 19.5 inch height
- Cooling only, no heat mode
ROVSUN 12000 BTU Inverter Window Air Conditioner
This ROVSUN window air conditioner uses inverter technology for efficient, quiet cooling. With 12000 BTU capacity, it covers rooms up to 520 square feet. Its sleep mode operates at 42 dB, making it suitable for bedrooms.
Pros
- Inverter technology for energy efficiency
- 42 dB sleep mode
- Covers up to 520 sq ft
- Pre-assembled installation kit
- Multiple operating modes
Cons
- Fits only windows with 14.5 inch height
- Heavy at 58.6 pounds
- Limited 1-year warranty
Windmill 10,000 BTU WhisperTech Window Air
Designed for quiet, efficient cooling in medium rooms, this window air conditioner covers up to 450 square feet with a whisper-quiet 40 dB operation. Its dual air intake design and inverter compressor enhance energy savings, while app and voice control provide convenient smart home integration. It is an excellent choice for bedrooms and other noise-sensitive spaces.
Pros
- Ultra-quiet 40 dB operation
- No-tools installation with kit
- Smart app and voice control
- Inverter compressor for efficiency
- Covers rooms up to 450 sq. ft.
Cons
- Fits only 19-inch wide windows
- Heavy at 71 pounds
- No heating function
Frigidaire 8,000 BTU Smart Inverter Window Air
This Frigidaire window air conditioner uses an inverter compressor to deliver steady cooling at 41 dB for quiet operation. The 8,000 BTU output covers rooms up to 350 square feet, and Wi-Fi enables app or voice control. It is a good choice for anyone who wants energy-efficient, smart cooling in a bedroom or small living room.
Pros
- Quiet operation at 41 dB
- Inverter compressor for energy savings
- Wi-Fi and app control
- Energy Star certified
- Washable filter with alert
Cons
- Heavy at 55 pounds, may need two people to install
- Requires window opening height of exactly 14 inches
- Only 1-year warranty
LG LW1024RSMX 10,000 BTU Window Air Conditioner
A 10,000 BTU window air conditioner that cools medium to large rooms up to 450 square feet. Its Wi-Fi connectivity and ThinQ app allow remote control and voice commands through Alexa or Google Assistant. The 4-way air deflection and three cooling speeds provide flexible airflow, while the slide-out washable filter simplifies maintenance.
Pros
- Smart control via ThinQ app and voice.
- 4-way air deflection for even cooling.
- Washable filter with reminder light.
- Easy installation with EZ Mount kit.
- Quiet operation at 52 dB.
Cons
- Fixed chassis; not slide-out design.
- Fits only double-hung windows.
- Cooling only; no heat pump mode.
Whirlpool 10,000 BTU Window Air Conditioner
For medium-sized rooms up to 450 square feet, the Whirlpool 10,000 BTU window unit delivers efficient cooling and dehumidification. It offers three cooling speeds, Eco and Sleep modes, and a programmable 24-hour timer for flexible comfort. Quiet operation and easy installation make it a practical choice for bedrooms, living rooms, and apartments.
Pros
- Cools up to 450 sq ft
- Energy Star rated (12.1 EER)
- Removable washable filter with Clean Alert
- Eco and Sleep modes
- Quiet operation
Cons
- Heavy at 63.9 pounds
- Confusing remote control symbols
- Controls hard to read
BLACK+DECKER 12,000 BTU Window Air Conditioner
The BLACK+DECKER 12,000 BTU window air conditioner cools up to 550 square feet with a CEER of 10.9. It offers three cooling and fan speeds, a remote control, and energy-saving features like sleep mode and timer. Suitable for large rooms, master bedrooms, and small apartments.
Pros
- Covers up to 550 sq ft efficiently
- Inverter compressor for stable cooling
- Remote control and digital display
- Sleep mode and timer for energy savings
- Includes installation kit and hardware
Cons
- Not Energy Star certified
- Noise level of 59 dB
- Heavy at 63.7 pounds
Hisense 10,000 BTU Window Air Conditioner
This window air conditioner delivers 10,000 BTU of cooling for rooms up to 450 square feet, with smart app control via ConnectLife for remote adjustments. Its three modes and four-way air direction help maintain even comfort, while a 2-year warranty adds peace of mind. Best suited for those who want a connected, mid-range unit with dehumidifier capability.
Pros
- Smart app control with remote and touch panel.
- Three operating modes for versatile use.
- Even air distribution with four-way direction.
- Easy maintenance with washable filter.
- 2-year warranty for added reliability.
Cons
- Noise level may disrupt TV at normal volume.
- Smaller physical size than some expect.
- Heavy at 50.7 pounds for installation.
Top 3 Conventional Window Air Conditioners Under $400 Reviewed
#1 Midea 8,000 BTU Smart Inverter Window Air Conditioner: Best Overall
Why We Picked It
The Midea MAW08S1VWT-A gives you an inverter compressor, ENERGY STAR certification and full smart control for a room up to 350 sq ft, and it backs that up with a 4.3 rating from 224 ratings, the strongest buyer record in this group. Midea lists it as low as 40 dBA, quiet enough for a bedroom or a home office where you take calls.
The inverter changes speed to hold the set temperature instead of switching fully on and off, so the room stays steadier and the unit uses less power over a long day. The listing gives a SEER of 14. Controls include an LED display, four modes (Auto, Cool, Dry and Fan), three fan speeds plus Auto, a 24-hour timer, an ECO setting, the SmartHome app and voice control. The installation bracket is included.
Key Specifications
- Cooling Capacity: 8,000 BTU
- Room Size: Up to 350 sq ft
- Noise Level: As low as 40 dBA
- Compressor: Inverter, ENERGY STAR certified
- Controls: SmartHome app, voice, remote, LED panel
- Window Fit: 23″ to 36″ wide, 19.5″ minimum height
| Pros | Cons |
|---|---|
|
|
Things to Consider
The 19.5 inch minimum window height is the tallest requirement in this group, so measure the open sash before you buy. At 43 pounds it is light for an inverter unit, and most people can install it with one helper.
Best For
This unit is best for a bedroom or office up to 350 sq ft where quiet running and lower energy use matter most.
Check the current price and availability of the Midea 8,000 BTU Smart Inverter Window Air Conditioner on Amazon.
Read our full Midea 8,000 BTU Smart Inverter Window Air Conditioner review.
#2 ROVSUN 12000 BTU Inverter Window Air Conditioner: Best for Large Rooms
Why We Picked It
The ROVSUN is the only 12,000 BTU inverter unit in this group, and it is rated for rooms up to 520 sq ft. That makes it the pick for a large living room, an open studio or a primary bedroom with a sitting area. It has a 4.1 rating from 159 ratings, and ROVSUN claims 35 percent energy savings over traditional units.
It is quiet for its size, with a listed 42 dBA in sleep mode, and 4-way swing spreads the air across a wide room. You set sleep mode, fan speed, a 24-hour timer, ECO, auto and fan modes from the LED panel or the remote. The side panels come pre-assembled, which ROVSUN says saves at least 30 percent of the usual install time.
Key Specifications
- Cooling Capacity: 12,000 BTU
- Room Size: Up to 520 sq ft
- Noise Level: 42 dBA in sleep mode
- Compressor: Inverter
- Controls: LED panel, remote, 24-hour timer
- Window Fit: 25″ to 36″ wide, 14.5″ minimum height
| Pros | Cons |
|---|---|
|
|
Things to Consider
The feature text lists a 15.0 CEER, while the specifications give a SEER of 12, so treat the efficiency claim with some caution. The window must be at least 25 inches wide, slightly wider than most units here need.
Best For
This unit is best for a living room or large bedroom of 450 to 520 sq ft where you want inverter cooling without going over $400.
Check the current price and availability of the ROVSUN 12000 BTU Inverter Window Air Conditioner on Amazon.
Read our full ROVSUN 12000 BTU Inverter Window Air Conditioner review.
#3 Windmill 10,000 BTU WhisperTech Window Air Conditioner: Best for Medium Rooms
Why We Picked It
The Windmill 10,000 BTU fills the gap between the 8,000 BTU Midea and the 12,000 BTU ROVSUN, cooling rooms of 350 to 450 sq ft. Its WhisperTech design pulls air in from the front and the bottom and sends cooled air out at a 45 degree angle, and the specifications list 40 dB, which ties the Midea for the lowest noise figure here. It has a 4.0 rating from 190 ratings.
Windmill also makes it easy to live with. The install kit comes pre-assembled and needs no tools, double-insulating side panels help keep cool air in and street noise out, and you get app and voice control. Filtration uses a washable mesh filter with an optional activated carbon filter, and the LEDs dim on their own at night.
Key Specifications
- Cooling Capacity: 10,000 BTU
- Room Size: 350 to 450 sq ft
- Noise Level: 40 dB
- Compressor: Listed as inverter in the specifications
- Controls: Windmill Air app, voice, remote
- Weight: 71.3 pounds
| Pros | Cons |
|---|---|
|
|
Things to Consider
The specifications list a 19 inch window width for both minimum and maximum, which does not match a 19.3 inch wide cabinet, so check Windmill’s install guide for the real range before you order. At 71.3 pounds you will need two people.
Best For
This unit is best for a living room or large bedroom of 350 to 450 sq ft where you want quiet running and a simple install.
Check the current price and availability of the Windmill 10,000 BTU WhisperTech Window Air Conditioner on Amazon.
Read our full Windmill 10,000 BTU WhisperTech Window Air Conditioner review.
Other Models Worth Considering
Frigidaire 8,000 BTU Smart Inverter Window Air Conditioner (FHWW085WE1). Like the Midea, it pairs an inverter with ENERGY STAR certification and covers 350 sq ft. It lists 41 dB, works with the Frigidaire app, Amazon Alexa and Google Home, and has 6-way airflow, three fan speeds, a Dry Mode and a 24-hour timer. It needs only a 14 inch window opening, but it weighs 55 pounds and has fewer ratings than the Midea.
LG 10,000 BTU Window Air Conditioner (LW1024RSMX). A standard-compressor unit for rooms up to 450 sq ft, with LG ThinQ app control, Google Assistant support, 4-way air deflection and three cooling and fan speeds. The EZ Mount kit fits double-hung windows 22 to 36 inches wide with a 13 inch opening. It lists 52 dB and has a 4.1 rating from 85 ratings.
Whirlpool 10,000 BTU Window Air Conditioner (WHAW101CW). This ENERGY STAR rated unit lists a 12.1 EER and removes up to 2.1 pints of moisture per hour, useful in humid climates. It has Eco and Sleep modes, a 24-hour timer, 8-way louvers and a remote. It is one of the louder units here at 59 dB and weighs 63.9 pounds.
BLACK+DECKER 12,000 BTU Window Air Conditioner (BWAC12WTB). The most capacity for the money in this group, rated for up to 550 sq ft with a 10.9 CEER. It has a digital display, a full-function remote, three speeds, Sleep and Energy Saver modes, and a warranty with five years of compressor parts coverage. The specifications give 450 sq ft for floor area, so size it conservatively.
Hisense 10,000 BTU Window Air Conditioner (AAW10CW26). It adds the ConnectLife app, a touch panel and a remote to a 450 sq ft unit, with cooling, fan and dehumidifier modes and four-way air direction. It lists 53 dB. The feature text promises a 2-year warranty while the specifications say one year, so confirm the terms with the seller.
What to Expect from Conventional Window Air Conditioners Under $400
The upper end of this budget is the first price tier where inverter window units are common. You can choose between a quiet, efficient 8,000 BTU inverter for a bedroom and a larger 10,000 or 12,000 BTU unit for a living room. Smart control is standard on most models here, and several are ENERGY STAR certified.
Window unit prices change through the season. All eight picks were at or under $400 when we checked, and the product cards show the current price. For a deeper look at this technology across all price points, see our guide to conventional window air conditioners with inverter compressors.
How to Choose a Conventional Window Air Conditioner Under $400
Choose Between Inverter Efficiency and Extra Capacity
Under $400 you often have to pick one. An inverter unit like the Midea or Frigidaire runs quieter and costs less to run, but tops out at 8,000 BTU here. A standard unit like the BLACK+DECKER or Whirlpool gives you 10,000 to 12,000 BTU for the same money. The ROVSUN is the one unit that offers both.
Size the Unit Correctly
ENERGY STAR publishes this general guide for sizing a room air conditioner by floor area:
| Room Size (sq ft) | Cooling Capacity (BTU/hr) |
|---|---|
| 100 to 150 | 5,000 |
| 150 to 250 | 6,000 |
| 250 to 300 | 7,000 |
| 300 to 350 | 8,000 |
| 350 to 400 | 9,000 |
| 400 to 450 | 10,000 |
| 450 to 550 | 12,000 |
| 550 to 700 | 14,000 |
| 700 to 1,000 | 18,000 |
Reduce capacity by 10 percent for a heavily shaded room, increase it by 10 percent for a very sunny room, and add 600 BTU for each regular occupant beyond two. Source: ENERGY STAR.
Measure the Window and Plan for the Weight
Minimum opening heights in this group range from 13 to 19.5 inches, and minimum widths from 22 to 26 inches. The 10,000 and 12,000 BTU units weigh 50 to 71 pounds, so you will want a helper and, on a shallow sill, a support bracket.
Match the Smart Features to Your Home
If you already use Alexa, Google Assistant or LG ThinQ, pick a unit that works with it. App control is most useful for cooling a room before you get home; for a bedroom, a sleep mode and a timer matter more.
How We Evaluate Conventional Window Air Conditioners
We rank conventional window air conditioners on manufacturer specifications, listing details and aggregated buyer ratings. For this list we kept only units listed at or under $400. We weighed room coverage, compressor type and buyer feedback first, with more weight on ratings from larger numbers of buyers, then compared noise, efficiency, controls, window fit, weight and warranty. Where a listing gives conflicting figures, we point it out and size against the more conservative number.
Frequently Asked Questions
Is an inverter window air conditioner worth it under $400?
For a room you cool every day or every night, usually yes. Inverter units like the Midea run as low as 40 dBA and hold a steadier temperature, and the lower power draw adds up over a summer.
What size window air conditioner under $400 cools a large living room?
Look for 12,000 BTU. The ROVSUN is rated for 520 sq ft and the BLACK+DECKER for up to 550 sq ft in its feature text.
Which unit is the quietest?
The Midea 8,000 BTU lists 40 dBA and the Windmill 10,000 BTU 40 dB, followed by the Frigidaire at 41 dB. The standard-compressor Whirlpool and BLACK+DECKER list 59 dB.
Do these units need a special outlet?
No. All eight are 115V units that plug into a standard household outlet. Larger units draw more power, so use a wall outlet on a circuit without other large appliances.
Final Verdict
The Midea 8,000 BTU Smart Inverter Window Air Conditioner is the best conventional window air conditioner under $400 for most bedrooms and offices, with an ENERGY STAR certified inverter, 40 dBA operation, full smart control and the strongest buyer record in the group. For a room up to 520 sq ft, the ROVSUN 12,000 BTU Inverter Window Air Conditioner brings inverter cooling to a larger space. For 350 to 450 sq ft, the Windmill 10,000 BTU WhisperTech Window Air Conditioner is quiet and easy to install. Measure your room and window opening first, then choose between inverter efficiency and extra capacity.
About the author
Daniel Brooks is a home cooling editor at WikiCooling, covering window, portable, through-the-wall and mini-split air conditioners, fans, and dehumidifiers. He researches cooling capacity, energy efficiency, noise levels, installation requirements, and buyer feedback to help homeowners choose the right unit for their room size, climate, and budget.