Room AC BTU
Get a quick air-conditioner sizing estimate from a room's square footage using the common 20 BTU-per-square-foot rule of thumb. Enter the floor area and read the target BTU rating. Adjust up for sunny rooms, high ceilings or many occupants.
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Worked example
BTU: 6,000 · Rule: ~20 BTU/ft²
Inputs
- Room ft²
300
Frequently asked
What does BTU mean here?
It's the cooling capacity rating of the AC unit; bigger rooms need a higher BTU number.
Is 20 BTU/ft² always right?
It's a starting point — add capacity for kitchens, sunny exposures or crowded rooms.