BTU Calculator

All tools

Find the right air conditioner or heater size for any room — enter your room dimensions, sun exposure and occupancy to get cooling BTU, tons and recommended AC size.

m
m
m
Cooling needed – BTU/h
Tons of cooling –
Recommended AC –
Heating needed –
Estimates use ~20 BTU/h per sq ft for cooling with adjustments for sun, ceiling height, occupants and kitchens (1 ton = 12,000 BTU/h). Confirm with an HVAC professional for installation.
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