Small window air conditioners start at 14” wide and 11” tall. Large window air conditioners are as wide as 28” and as tall as 22” – a few are taller.
There is one very low profile window AC, the Kapsul W5, which is only 7” tall – but delivers just 5,000 BTU of air conditioning (and is prohibitively expensive).
If you need a narrow window air conditioner, consider a casement window AC. They’re produced in 8,000 and 10,000 BTU with a narrow width of 15.5” or 16”.
Window Air Conditioner Dimensions
Here is a window AC size chart from 5,000 to 35,000 BTU window air conditioners.
Window Air Conditioner Dimensions
Cooling Capacity | Width | Height | Depth |
5,000 Btu | 15 – 20 Inches | 7 – 15 Inches | 12 – 23 Inches |
6,000 Btu | 14 – 21 Inches | 11 – 20 Inches | 12 – 24 Inches |
6,200 Btu | 16 – 21 Inches | 12 Inches | 18 Inches |
8,000 Btu | 14 – 26 Inches | 12 – 24 Inches | 12 – 29 Inches |
8,200 Btu | 24 Inches | 15 Inches | 22 Inches |
9,500 Btu | 20 Inches | 12 – 14 Inches | 21 – 25 Inches |
10,000 Btu | 14 – 26 Inches | 13 – 22 Inches | 16 – 29 Inches |
11,000 Btu | 23 Inches | 15 Inches | 23 Inches |
12,000 Btu | 19 – 26 Inches | 13 – 22 Inches | 16 – 29 Inches |
13,600 Btu | 26 Inches | 16 – 18 Inches | 29 Inches |
14,000 Btu | 19 – 24 Inches | 15 – 16 Inches | 21 – 29 Inches |
14,500 Btu | 19 – 21 Inches | 15 – 19 Inches | 15 – 22 Inches |
15,000 Btu | 20 – 26 Inches | 15 – 18 Inches | 23 – 28 Inches |
17,500 Btu | 26 Inches | 18 Inches | 29 Inches |
18,000 Btu | 20 – 26 Inches | 15 – 24 Inches | 18 – 31 Inches |
20,000 Btu | 26 Inches | 18 Inches | 29 Inches |
21,500 Btu | 26 Inches | 18 Inches | 29 Inches |
22,000 Btu | 26 Inches | 18 Inches | 26 Inches |
23,000 Btu | 26 – 28 Inches | 17 – 20 Inches | 31 – 36 Inches |
23,500 Btu | 26 Inches | 18 Inches | 26 – 31 Inches |
24,000 Btu | 26 – 28 Inches | 19 – 20 Inches | 26 – 36 Inches |
24,500 Btu | 26 Inches | 18 Inches | 28 Inches |
25,000 Btu | 27 Inches | 19 – 27 Inches | 19 – 27 Inches |
28,000 Btu | 27 – 28 Inches | 19 – 20 Inches | 27 – 36 Inches |
35,000 Btu | 28 Inches | 20 Inches | 36 Inches |
Note: This data is based on 212 popular window ACs on the market.
That’s right. We have done the research looking at more than 200 window air conditioner models to produce the most comprehensive list of window AC dimensions.
Minimum & Maximum Window Width for Window AC Installation
The minimum window width of a window air conditioner is 15.5” for a casement window air conditioner and 21” for a standard window air conditioner.
The maximum window width of a window air conditioner is 41”.
The max width accounts for the side panels fully extended.
Cooling Capacity | Minimum Window Width | Maximum Window Width |
5,000 Btu | 21 Inches | 38 Inches |
6,000 Btu | 21 Inches | 36 Inches |
6,200 Btu | 27 Inches | 39 Inches |
7,500 Btu | 22 Inches | 36 Inches |
8,000 Btu | 15.5 Inches (casement) | 36 Inches |
8,200 Btu | 23 Inches | 36 Inches |
10,000 Btu | 16 Inches (casement) | 39 Inches |
10,200 Btu | 22 Inches | 36 Inches |
12,000 Btu | 23 Inches | 39 Inches |
14,000 Btu | 24 Inches | 40 Inches |
15,000 Btu | 28 Inches | 41 Inches |
18,000 Btu | 28 Inches | 41 Inches |
22,000 Btu | 29 Inches | 41 Inches |
23,000 Btu | 29 Inches | 41 Inches |
23,500 Btu | 30 Inches | 39 Inches |
24,000 Btu | 30 Inches | 41 Inches |
24,500 Btu | 29 Inches | 41 Inches |
The minimum width for 8,000 and 10,000 BTU window air conditioners includes casement window ACs designed to be narrow enough for use with a casement window. Some of these can also be used in sliding or gliding windows.
For standard window ACs that fit into single-hung and double-hung windows, the minimum width is around 21” to 23” depending on AC BTU capacity.
Can you put an air conditioner in a small window?
Yes, but it will have to be a window AC with 5,000 to 8,000 BTU capacity max.
Minimum Window Height for Window Air Conditioner Installation
Minimum window height is 12” to 20”.
This means the window must open at least this much to provide room for the AC.
Minimum Window Height for Window Air Conditioner Installation
Cooling Capacity | Minimum Window Height |
5,000 Btu | 7 Inches |
6,000 Btu | 12 Inches |
6,200 Btu | 14 Inches |
7,500 Btu | 14 Inches |
8,000 Btu | 13 Inches |
8,200 Btu | 16 Inches |
10,000 Btu | 14 Inches |
10,200 Btu | 16 Inches |
11,000 Btu | 17 Inches |
12,000 Btu | 14 Inches |
14,000 Btu | 16 Inches |
15,000 Btu | 19 Inches |
18,000 Btu | 18 Inches |
22,000 Btu | 19 Inches |
23,000 Btu | 18 Inches |
23,500 Btu | 20 Inches |
24,000 Btu | 20 Inches |
25,000 Btu | 20 Inches |
28,000 Btu | 20 Inches |
What is the smallest height window air conditioner?
7” – and only the Kapsul W5 is 7”. Others are higher.
There are very few low profile window air conditioners less than 12” in height.
10 – 16 Inches Height Low Profile Window Air Conditioners
How high does a window open for an AC?
At least 7”, but most window ACs need 12” of height or more.
10 – 16 inches height Low Profile Window Air Conditioners
10 inch height window AC
11 inch height window AC
- N/A or None Available
12 inch height window AC
- LG LW6017R
- Kenmore 87050
- GE AEL05LX
- Frigidaire FFRA051WAE
- Keystone KSTAW05CE
13 inch height window AC
- Toshiba RAC-WK0511CMU
- Midea MAW05R1BWT
- Danby DAC050MB1WDB
- Frigidaire FFRE053WAE
- GE AHEC05AC
- Haier QHEC05AC
14 inch height window AC
- Midea MAW05R1WBL
16 inch height window AC
- Della 048-TL-WAC5K
As you can see, you have options. Make sure to accurately measure the window opening to know the most narrow or the minimum window opening to accommodate an AC.
How Do You Measure a Window for an Air Conditioner?
The dimensions are given in width x height. If there is a third dimension, it is the depth.
1 – Open the window fully
2 – Use a tape measure to measure the width of the window at the most narrow part
3 – Measure the height of the window opening from the bottom of the window sash to the highest point of the windowsill
In short, measure the window side to side and top to bottom. Make sure the window air conditioner you choose fits inside those window dimensions.
What Is the Standard Size of a Window Air Conditioner?
16” to 26” wide by 12” to 18” high.
There are more narrow units available. Taller units are usually casement window air conditioners.
Here are average sizes.
- 6,000 BTU: 14” to 21” wide x 11” to 20” high
- 8,000 BTU: 14” to 26” wide x 12” to 24” high (including casement ACs)
- 10,000 BTU: 14” to 26” wide x 13” to 22” high (including casement)
- 12,000 BTU: 19” to 26” wide x 13” to 22” high
- 15,000 BTU: 20” to 26” wide x 15” to 18” high
- 18,000 BTU: 20” to 26” wide x 15” to 24” high
- 20,000 BTU: Average 26” wide x 18” high
- 24,000 BTU: 26” to 28” wide x 19” to 20” high
- 35,000 BTU: Average 28” wide to 20” high
FAQ
How much space is needed behind a window AC?
Between 8” and 18”.
Determine if a window air conditioner will fit in your space when depth is limited. To do this, measure the part of the AC that will stick outside the window.
Do window air conditioners fit all windows?
No. Measure your window opening for minimum width and height requirements. And then check the specs on the AC. The information on most product pages or AC boxes tell you what the minimum and maximum window openings are for the unit.
If you want to put a window AC in a casement window, you’ll need to choose a unit called a casement window AC. It will be narrow but taller than most other window air conditioners.
What should be the size of window for window AC?
At least 21” wide and 12” high.
But a window with a wider frame and one that opens more than 12” will allow you to use a larger size AC.
Can a window be too big for AC unit?
Yes. A window can be too wide and too high for an air conditioner.
Too wide: When the side panels of an AC are fully opened, total width is 38” to 41”. If the window is wider, you will need to fill the gap between the panels and the window frame with plastic, insulation or other material that blocks air leaks.
Too tall: If you want a unit in a casement window, first choose one designed for that window type. Even then, the panels provided might not fill the space above the AC, and you will have to improvise to stop issues like air leaks and insects.
What is a casement window air conditioner?
It is a window AC with a narrow width and taller profile. The AC is designed to fit in a casement window rather than a sash window that opens vertically. Height is greater than width unlike more window air conditioners.