Air Conditioner Size Calculator

Estimate cooling capacity and recommended class from floor area

Cooling Space
Recommended class
~0 pyeong
Details
Floor area10.0 pyeong (33.1 ㎡)
Required capacity4,500 W
In BTU15,354 BTU/h
Recommended class11평형 (pyeong-class)
⚠️ Reference estimate based on typical cooling load per area. The capacity you actually need depends on insulation, floor and orientation, window area, occupants and appliance heat, so consult the maker or installer before buying. calcstool.com assumes no liability for these results.
FAQ
How is air conditioner size calculated?
Multiply the cooling floor area (in pyeong) by about 450 W per pyeong for homes (580 W for commercial) to get required capacity (W), then divide by 400 W for the product "class". One pyeong is about 3.3058 ㎡.
How do W and BTU relate?
1 W is about 3.412 BTU/h. So 4,500 W is roughly 15,400 BTU/h.
What about a living-room stand unit?
Living rooms often open to the kitchen, so size for about 1.3× the actual area; for large windows, west-facing or top-floor rooms, go one or two classes higher. The adjustment option adds +20%.

Air Conditioner Sizing

An AC "class" (pyeong-class in Korea) is the area a unit can cool efficiently. Undersizing makes the compressor run constantly and raises power bills; oversizing wastes money. This tool estimates the right size from your floor area.

Method

Area (pyeong) × capacity per pyeong (≈450 W home, ≈580 W commercial) = required capacity (W). Product class = capacity ÷ 400 W. For high-load rooms (large glazing, west sun, top floor), add 20% and consider one class up.

Reference

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