How big is a window air conditioner?#
A window air conditioner is a box 16 to 27 inches wide and 12 to 19 inches tall, sized to the window opening it fills. The table below sorts the small, medium, and large units.
Window air conditioner dimensions by configuration#
| Configuration | Width (in) | Height (in) | Depth (in) | Best for |
|---|---|---|---|---|
| Small window air conditioner | 16–20 | 12–14 | 15–18 | a bedroom or small room |
| Medium window air conditioner | 19–24 | 14–16 | 19–24 | a living room or open area |
| Large window air conditioner | 24–27 | 16–19 | 22–27 | a big room or a small apartment |
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Installation clearances for a window air conditioner#
- Window opening width: 16–27 in in of open window width a window air conditioner needs, matched to the unit body.
- Sill depth: 15–27 in in the window air conditioner body extends back into the room and out the window.
- Side curtains: A window air conditioner seals the leftover opening with accordion side curtains that expand to the window jamb.
- Support bracket: A heavy window air conditioner needs an exterior support bracket so the sill does not carry all the weight.
Will your window air conditioner fit? Clearances and door swing#
The whole fit hinges on the window, not a floor clearance. Match the unit body to a 16 to 27 inch open window width so the cabinet seats in the opening, and remember the body extends 15 to 27 inches back — part into the room and part out the window. The accordion side curtains expand from the unit to the window jambs to seal the leftover gap, so the opening cannot be wider than the curtains reach. A heavier medium or large unit needs an exterior support bracket so the window sill is not carrying all the weight, which is a code and safety point on upper floors. Measure the window's open width and the sill depth before buying, and confirm the sash can close down onto the unit's top flange.
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Window air conditioner sizes by type: small window air conditioner, medium window air conditioner, large window air conditioner#
The three sizes scale cooling to the room. The small unit, 16 to 20 inches wide and 12 to 14 tall, cools a bedroom or small room and is light enough to sit on the sill without a bracket in many windows. The medium unit grows to 19 to 24 inches wide and 14 to 16 tall for a living room or open area, and its weight usually calls for a support bracket. The large unit, 24 to 27 inches wide and 16 to 19 tall, handles a big room or a small apartment and definitely needs an exterior bracket. Match cooling capacity to the room, then confirm the window opening and sill can take the unit.
Window air conditioner dimensions: common questions#
What size window opening does a window air conditioner need?#
The unit needs a 16 to 27 inch open window width matched to its body, with the side curtains sealing the rest. Measure the open sash width before choosing a model.
How deep does a window air conditioner sit in the room?#
The body extends 15 to 27 inches front to back, split between the room side and outside the window. A large unit reaches the deepest at 22 to 27 inches.
How tall is a window air conditioner?#
Height runs 12 to 19 inches. A small bedroom unit is shortest at 12 to 14 inches, while a large unit is 16 to 19 tall.
Does a window air conditioner need a support bracket?#
A heavier medium or large unit needs an exterior support bracket so the sill does not carry all the weight, which matters for safety on upper floors. A light small unit often sits on the sill alone.
How wide is a large window air conditioner?#
A large window air conditioner is 24 to 27 inches wide for a big room or small apartment. It is the widest of the three and needs a support bracket.
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