Before you buy a window unit, you have to check the window AC dimensions in inches. Just can’t just get a window air conditioner and hope it fits on your window sill. *Adequately* estimating window AC frame size – that’s **window AC width and height** – and fitting it to your window help you avoid a lot of troubles.

*Note:* If you are **based in India**, you will probably need to convert window AC centimeters to inches.

First of all, you have to measure the size of the window you want to install a window AC on. Measure both the length (most important) and height of your window (less important).

Once you roughly know what size window you have (Example: “I have 38×26 inch window”), you can start looking at window AC size in inches.

*What are the average dimensions of window air conditioners?*

There are 3 key window AC dimensions you should check:

**Minimum window length**in inches.*Example:*If you want to install a 1-ton window AC unit, you would need at least a**23-inch**wide window.**Maximum window length**in inches. You have to install window AC kits (left and right from the unit) to cover the window.*Example:*Maximum window length for most 1-ton window air conditioners is**36 inches**.**Minimum window height**in inches. Windows have to be sufficiently high to be suitable for an AC unit.*Example:*For installing a 1-ton window AC unit, you need at least**15.5 inches high**window.

*What window type aircon dimensions you are looking for (given AC capacity)?*

To help you adequately fit a new window AC unit, we have prepared example tables with window air conditioner dimensions in inches (real units currently on the market) for different AC capacities, including:

**1-ton**window air conditioner size in inches.**1.5-ton**window air conditioner size in inches.- A complete table of window AC dimensions from the
**smallest 5,000 BTU capacity to the biggest 25,000 BTU capacity**.

Note: If you would like a recommendation for a good window AC unit with certain dimensions, you can use the comments below the article, specify the designed dimensions, and we can help you out by recommending a unit.

Let’s first look at the dimensions of the most widely spread 1-ton and 1.5-ton window aircon. You will find a complete table of window AC dimensions (from below 1-ton to above 2-ton units) further on:

## 1 Ton Window AC Size In Inches

1-ton or 12,000 BTU window AC units are quite popular. The minimum window length you need for a 1-ton window AC unit is ** 23 inches**. You will rarely find a 1-ton unit that can be installed in a narrower window frame (exceptions are these vertical window AC units here with min. length of about 15.5 inches).

To give you an idea of what are the dimensions of 1-ton window AC units and the window dimension requirement, we have looked at some 12,000 BTU window AC units currently on the market. These are minimum and maximum window lengths and minimum window heights for 1-ton window AC units:

Window AC Unit: |
Min. Window Length: |
Max. Window Length: |
Min. Window Height: |

LG LW1216ER | 24 Inches |
36 Inches |
16 Inches |

Voltas 23 Lyi/123 LZF | 23 Inches |
36 Inches |
15.5 Inches |

Carrier CAW12ET3N8F0 | 24 Inches |
36 Inches |
16 Inches |

MIDEA MAW12R1BWT | 23 Inches |
36 Inches |
14 Inches |

Amana AMAP121BW | 23 Inches |
38 Inches |
15.5 Inches |

BLACK+DECKER BD12WT6 | 23 Inches |
36 Inches |
15.5 Inches |

Emerson Quiet Kool | 23 Inches |
36 Inches |
15.5 Inches |

We can look at LG 1-ton window AC size in inches. It’s quite a representative unit because it has standard-size dimensions for a 1-ton unit.

LG LW1216ER (1-ton unit) can be installed on windows that have:

- At least 24 inches in length and at most 36 inches in length.
- Have a minimum height of at least 16 inches.

This is the correct window frame we are looking for when installing most 1-ton units. On top of the dimensions of the 1-ton window AC unit, you have to add:

- A minimum of
**0.2 inches on left and right**. - A minimum of
**0.5 inches on the top**of the unit. Example: Window AC height is 15 inches but you will need at least 15.5-inch window height to install it correctly.

Let’s have a look at a 1.5-ton AC unit dimensions:

## 1.5 Ton Window AC Size In Inches

Another popular choice are 1.5-ton or 18,000 BTU window air conditioners.

*What is the average window AC 1.5-ton size in inches?*

On average, 1.5-ton window AC units require a window width of **at least 27 inches**. Due to the limitation of most installation kits (window seals of left and right), the maximal window length is about 42 inches.

Here are specific 1.5-ton window air conditioners currently on the market with the required window dimensions in inches:

Window AC Unit: |
Min. Window Length: |
Max. Window Length: |
Min. Window Height: |

LG LW1817IVSM | 27.5 Inches |
42 Inches |
18.5 Inches |

KEYSTONE KSTHW18A | 27 Inches |
42 Inches |
19 Inches |

LG LW1821HRSM | 27 Inches |
42 Inches |
15 Inches |

Voltas 183 DZA/ 183 DZA | 28 Inches |
44 Inches |
19 Inches |

Hitachi RAW518KUDZ1 | 27.5 Inches |
42 Inches |
18.5 Inches |

Blue Star 5W18GBT | 27.5 Inches |
42 Inches |
18.5 Inches |

Here is an example of LG 1.5 ton window AC size in inches:

If you check the LG 1.5 AC size and window requirements, you notice that:

- Has a 25.98-inch length. The specified minimum window length requirement is 27.5 inches and the maximum window length requirement is 42 inches.
- Has a 17.72-inch height. The minimum requirement window height is 18.5 inches.

Let’s look at some other tonnages:

**0.75-ton window AC size**unit requires a minimum window length of**22 inches**and a maximum window length of 36 inches.**2-ton window AC size unit**requires a minimum window length of**28 inches**and a maximum window length of 44 inches.

To get the full picture, we have to look at the window AC capacities in BTUs:

## Window AC Sizes In Inches (5,000 – 25,000 BTU)

As we have talked about in portable vs window AC unit comparison, window AC units have quite a range as far as capacity is concerned. They can generate anywhere between 5,000 BTU (smallest window AC units with less than 0.5-ton capacity) and 25,000 BTU (biggest window AC units with more than 2-ton capacity).

The smallest LG LW6017R 5,000 BTU air conditioner has these dimensions: *14.38 x 17.31 x 11.13 inches* for Length x Width X Height. It requires at least 21 inches wide window and at most 35 inches wide window (to fit the window seal). It requires smaller windows.

The biggest FRIGIDAIRE FFRE253WAE 25,000 BTU has these enormous dimensions: *26.5 x 26.5 x 18.6 inches* for for Length x Width X Height. It requires big windows that are at least 28 inches long and up to 44 inches long.

Here is a rough estimate of how what window size you need for window AC units with specific capacity:

Window AC Capacity: |
Min. Window Length: |
Max. Window Length: |

5,000 BTU | 21 Inches |
35 Inches |

6,000 BTU | 21 Inches |
35 Inches |

8,000 BTU | 22 Inches |
36 Inches |

10,000 BTU | 22 Inches |
36 Inches |

12,000 BTU | 23 Inches |
36 Inches |

14,000 BTU | 25 Inches |
38 Inches |

15,000 BTU | 25 Inches |
38 Inches |

18,000 BTU | 27 Inches |
42 Inches |

20,000 BTU | 27 Inches |
42 Inches |

22,000 BTU | 28 Inches |
44 Inches |

24,000 BTU | 28 Inches |
44 Inches |

25,000 BTU | 28 Inches |
44 Inches |

You might notice a bigger jump after 15,000 BTU. *Example:* 15,000 BTU window AC unit has a minimum window length of 25 inches and the 18,000 BTU window AC requires a minimum 27 inches long window. You can also see that the maximum window length jumps from 38 inches to 42 inches.

This is due to the higher **230V voltage** used in all 15,000+ BTU window air conditioners. Smaller 15,000 BTU or smaller units run on the standard 110/120V voltage. This difference in voltage does increase the overall size of a window air conditioner somewhat.

Now, a lot of people ask us to find them something like a 20-inch wide window air conditioner. Let’s address this as well

## 14 To 40 Inch Wide Window Air Conditioners

In our experience, homeowners also search for these units:

**14-inch**wide window air conditioner.**16-inch**wide window air conditioner.**17-inch**wide window air conditioner.**18-inch**wide window air conditioner.**20-inch**wide window air conditioner.**24-inch**wide window air conditioner.**28-inch**wide window air conditioner.- Even a
**40-inch**wide window air conditioner.

It’s understandable why these questions occur. All window AC dimension sizing should start with measuring your window dimensions. If you measure that you have a 20-inch or 24-inch window, you then start looking for a 20-inch wide or 24-inch wide window air conditioner.

You can use the table of 5,000 BTU to 25,000 BTU window AC dimensions above for help. Here’s how you can find a window air conditioner with certain width:

**For below 21 inches window width**, you won’t find the standard horizontal window air conditioners. You can check for vertical air conditioners (which are taller but slimmer). These units require the windows to be at least 15.5 inches wide; that’s a lot less than 15 inches. You can check these best narrow vertical air conditioners here.**For window AC units with 21+ inch width**, you should consult the before mentioned table above. Make sure that your window is not too wide as well.**For something like 40-inch wide window AC units**, you don’t have to worry about the minimum width. You have to instead focus on the maximum length. Window air conditioners below 15,000 BTU have the maximal window length requirement of less than 40-inches. You can’t install a very small window AC unit on a very wide window. This is, in fact, the only time this maximum required length is considered a limiting factor for installing a window air conditioner.

With the known window AC unit dimensions, you can now pick the right size AC unit with a bit more confidence. We hope you find all this helpful.

I have a specific opening that I need to find a new unit. I currently have an attic king 18,500. The space I’m cooling is appx 800 sq ft. The dimensions I need are 23 5/8 width and 17 3/8 height. Could go smaller but larger isn’t an option unless we are talking 1/8-1/4 inch.

Hello Chad, we are not aware of an 18,500 BTU window AC unit that would be so small. It’s extremely difficult to create such a big cooling output window AC unit with reduced dimensions from an engineering standpoint.

How do you know when your 5000 BTU Window units need Freon ? And is that something I can do myself and learn how to do it

Hello Deborah, we have an article about how to charge window AC with freon here. It’s usually done by professionals, we specify how that’s done, hope it can be of some help.

We had an LG 18,000 btu that was 17″ high. it had a slide out chassis that slipped easily into our window that has an opening of 30 wide by 17.25 high. Why can’t an a/c less than 17″ inches high fit into my window?

Hello Tess, well, if your windows are 17.25 high, you can easily use a window air conditioner with less than 17 inches height. It shouldn’t be a problem fitting that into the window.

Trying to cool a 432 SF cabin with window unit in centrally located window that needs a max 41 inch wide unit. What brand and model do you recommend? Would prefer Energy Star and 115V 3 prong plug for existing outlet. Would also prefer least amount of depth, multiple fan, speeds, remote, programmable, thermostat, dehumidifier component, and no requirement of support bracket. Thanks for your help.

Hello Cindy, for a 432 sq ft cabin you would require a window AC unit with 10,000 to 12,000 BTU cooling capacity. 12,000 BTU is the safer option given that cabins have below-average R insulation values. A good choice for all the preferences you specified would be the LG LW8017ERSM-P 12,000 BTU unit here; it has the Energy Star label, 3 speeds, 115V voltage, dehumidification function, and so on. Hope this helps.

I have an opening16”highx24” wide.

Hi Ruth, you can find many window AC units that will fit that window dimensions. Just make sure that the height is 15 inches and width is 23 inches; you want to leave that 1 inch space there just to be sure the unit will fit well.