Room size, climate, insulation, and sun in — cooling BTU, heating BTU, and the right tonnage out. Then send it straight into a quote.
Ballpark, not gospel. This estimates load from the numbers you punch in — run a proper Manual J calculation and check local code before sizing equipment or quoting a system.
Straight answers, no fluff. Then run your own numbers above.
Roughly 20,000 BTU, or about 1.7 tons — so a 2-ton unit. The rule of thumb is 20 BTU per square foot for cooling, adjusted up for hot climates, poor insulation, sunny rooms, and kitchens. Punch your exact space into the calculator above for a number that accounts for all of that.
For cooling, about 20 BTU per square foot is the standard starting point. For heating, it runs 25–50 BTU per square foot depending on climate — around 25 in mild regions, 35 in moderate ones, and 50 where winters are harsh.
Yes. An oversized AC cools the air too fast and shuts off before it dehumidifies — leaving the space cold and clammy, and short-cycling wears the compressor out faster. Slightly undersized beats oversized for comfort; the calculator rounds up only to the nearest half ton.
In the US, a full system replacement typically runs $2,500–$4,000 per ton installed, depending on equipment efficiency (SEER2 rating), ductwork condition, and region. A 3-ton system commonly lands $7,500–$12,000 all-in.
Got your tonnage? Turn this estimate into a professional HVAC quote and send it before you leave the job site.