CALCULATOR > AIR-CONDITIONER SIZE Discover the best air-conditioner size for your needs.

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Kindly input the size of your room and the number of its occupants.


Here are the results

Recommended Cooling Capacity (Air-conditioning Unit Size) For Your Room

For efficient use of electricity, you will need an air conditioning unit with cooling capacity of

0.00 kJ/hr

or 0.00 kW

or 0.00 Btu/hr

Conversion factor used:
1 kJ/hr = 0.000278 kW
1 kJ/hr = 0.947817 Btu/hr

How to check the air conditioning unit cooling capacity?


With standard height of 3 meters based on The American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) ; 1.0 met = 58.2 W/m² (18.4 Btu/h·ft²), which is equal to the energy produced per unit surface area of an average person seated at rest. The surface area of an average person is 1.8 m² (19 ft²) ; Using 1.35 met as average metabolic rate for common activities such as sitting, standing, sleeping, typing, walking, among others ; Based on ANSI/ASHRAE Standard 55-2017, Thermal Environmental Conditions for Human Occupancy.

Better way of determining the Right Air-conditioner Size through the Cooling Capacity

In the Philippines, the conventional way of expressing the size of an air-conditioning unit would be in "HP or Horsepower" and "TR or Tons of Refrigeration". However, DOE recommends selecting / buying an air-conditioning unit based on the Cooling Capacity indicated as kilojoule per hour (kJ/hr), kilowatt (kW) or British Thermal Unit per hour (Btu/hr) as this is a more precise measurement of how much cold air can the air-conditioning unit deliver in an hour.

To further explain, a 2 HP air-conditioning unit from Company X and a 2 HP air-conditioning unit from Company Y could have a different delivery rate of cold air (Cooling Capacity). Hence it would be better to use the Cooling Capacity (kJ/hour, kW or Btu/hr) when identifying the unit that is fit for your space.

The Calculator presents the results in kJ/hr, kW and BTU/hr so that consumers may be able to readily identify the cooling capacity in the product nameplate in any unit of measurement used.

Choosing the Right One

When buying an air-conditioning unit, choose the one with the same or slightly higher cooling capacity, as what was computed in the Air-conditioner Size Calculator. A slightly higher cooling capacity can provide additional coolness needed, especially during dry or summer season.

Consumers can just check the product’s nameplate, located in either the side or back of the unit, or the DOE Energy Label, which is attached to the actual unit, to identify the cooling capacity of the specific product.