Cooling · HP sizing
Aircon size calculator
In a tropical climate, plan 600–800 BTU per square metre: a 12 sq m bedroom takes a 0.75–1.0 HP aircon, a 20 sq m living room 1.5–2.0 HP. Enter your room below for the exact figure in BTU, then match it to the HP rating in the table.
Room dimensions
- Tons
- 1.35 t
- Kilowatts
- 4.75 kW
- Horsepower
- 2.03 HP
- Room area
- 12 m²
- Room volume
- 32.4 m³
Cooling capacity
16,200BTU/h
≈ 1.35 tons · 4.75 kW
060,000
HP to BTU and room size
Capacities as sold across the Philippines, Malaysia and Singapore. Room coverage uses the tropical 600–800 BTU per square metre rule.
| HP | BTU/h | kW cooling | Room size |
|---|---|---|---|
| 0.5 | 5,000 | 1.5 | 6–8 sq m |
| 0.75 | 7,000 | 2.1 | 9–12 sq m |
| 1.0 | 9,000 | 2.6 | 11–15 sq m |
| 1.5 | 12,000 | 3.5 | 15–20 sq m |
| 2.0 | 18,000 | 5.3 | 23–30 sq m |
| 2.5 | 24,000 | 7 | 30–40 sq m |
| 3.0 | 30,000 | 8.8 | 38–50 sq m |
The rule
BTU = floor area (sq m) × 600…800 shaded room → 600, sunny room → 800
HP = BTU ÷ 9,000 as labelled in PH, MY and SG
kW = BTU ÷ 12,000 × 3.52The calculator above works from room volume instead of floor area, so a high ceiling raises the answer as it should. Working in square feet and BTU instead? Use the AC size calculator.
FAQ
- What size aircon do I need for my room?
- In a tropical climate, plan 600–800 BTU per square metre. A 12 sq m bedroom needs roughly 7,000–9,000 BTU — a 0.75 to 1.0 HP split. A 20 sq m living room needs about 12,000–16,000 BTU, so 1.5 to 2.0 HP.
- How many HP is 1 aircon?
- In the Philippines, Malaysia and much of Southeast Asia, 1 HP of aircon is about 9,000 BTU/h. The common ladder runs 0.5 HP (5,000 BTU), 0.75 HP (7,000), 1.0 HP (9,000), 1.5 HP (12,000), 2.0 HP (18,000) and 2.5 HP (24,000).
- Is HP the same as electrical horsepower?
- No. On an aircon, HP labels the cooling capacity, not the motor power or the electricity drawn. A 1 HP unit delivers roughly 2.6 kW of cooling while consuming somewhere near 0.8–1 kW of electricity — and less than that on an inverter once the room is cool.
- Does a sunny room change the size?
- Yes. A room taking direct afternoon sun, sitting under an uninsulated roof, or with wide glass needs about 20% more capacity — usually the next HP step up. The calculator has a toggle for it.
- Should I get a window type or a split?
- That is a mounting and noise decision rather than a sizing one — the capacity you need is the same either way. Window types are cheaper to install; splits are quieter indoors and available in inverter models that cost less to run.