Aircon BTU, HP, Ton and kW Conversion Chart

Air conditioners are sold in four different units depending on the market. This chart lines all of them up against each other.

Convert Any Aircon Unit
Aircon size
HP

The same air conditioner is quoted four different ways depending on where it is sold. A machine listed as 12,000 BTU in an online spec sheet is a 1.5 HP unit in Manila, a 1 ton unit in Delhi, and a 3.5 kW unit in Sydney. Nothing about the hardware changes — only the yardstick.

The anchors: 1 ton = 12,000 BTU/hr exactly · 1 aircon HP ≈ 9,000 BTU/hr · 1 kW cooling = 3,412 BTU/hr.

Master Conversion Chart

Room-size figures assume a 2.7 m ceiling with moderate sun, using the 500 BTU/hr per square metre planning rule.

BTU/hrAircon HPTons (TR)Cooling kWRoom size
5,0000.5 HP0.421.4710 m²
7,0000.75 HP0.582.0514 m²
9,0001 HP0.752.6418 m²
12,0001.5 HP1.003.5224 m²
18,0002 HP1.505.2836 m²
24,0002.5 HP2.007.0348 m²
30,0003 HP2.508.7960 m²
36,0004 HP3.0010.5572 m²
48,0005.5 HP4.0014.0796 m²
60,0006.5 HP5.0017.58120 m²

Which Market Uses Which Unit

UnitWhere it is standardTypical phrasing
HorsepowerPhilippines, Malaysia, Indonesia"1.5 HP split type"
Tons / TRIndia, Middle East, North America"1.5 ton inverter AC"
BTU/hrSpec plates worldwide"12,000 BTU/hr cooling"
Cooling kWEurope, Australia, Japan"3.5 kW reverse cycle"

BTU/hr is the safest common denominator when cross-shopping, because virtually every manufacturer publishes it regardless of how the unit is marketed locally.

The Catch With Horsepower

Three of these four units are exact. Tons, BTU and kW convert between each other with fixed factors and no ambiguity. Horsepower is the odd one out — it is a market convention, not a defined unit, and it does not divide cleanly into the others.

The rough rule is 9,000 BTU per horsepower, but manufacturers build to a fixed ladder of model sizes rather than to that arithmetic. So 12,000 BTU calculates to 1.33 HP yet sells as 1.5 HP, and 24,000 BTU calculates to 2.67 HP yet sells as 2.5 HP. The chart above shows the sizes actually sold, which is what you need when buying.

A second trap: generic unit converters will tell you 12,000 BTU is 4.72 horsepower. That is the thermodynamic conversion using 2,544 BTU/hr per mechanical horsepower, and it is correct physics — but no air conditioner on earth is sold that way. Our BTU to HP calculator shows both figures side by side and explains the difference.

Going Deeper on Each Conversion

For a single conversion in a specific direction, these are the dedicated tools: BTU to HP, ton to HP, tonner to HP, cooling kW to HP and HP to ton. To size a unit against an actual room rather than a chart, use the aircon HP by room size calculator.

How this calculator is checked

Ton conversions use the exact definition 1 ton of refrigeration = 12,000 BTU/hr. Cooling kW uses 1 kW = 3,412.14 BTU/hr. Aircon horsepower follows the market convention of approximately 9,000 BTU/hr per HP, rounded to the model sizes actually manufactured. Room-size figures use the 500 BTU/hr per square metre planning rule at a 2.7 m ceiling height and are indicative rather than a substitute for a full heat-load survey.

Frequently Asked Questions

Exactly 12,000 BTU/hr. This is a defined conversion, derived from the heat needed to melt one short ton of ice over 24 hours.

A 1.5 HP unit is about 12,000 BTU/hr, which is roughly 3.52 kW of cooling. That is output, not electricity consumed.

No. One ton is 12,000 BTU/hr; one aircon HP is about 9,000 BTU/hr. One ton is roughly 1.33 HP by arithmetic and sells as 1.5 HP.

Two different scales share the name. The aircon convention is ~9,000 BTU/hr per HP; the thermodynamic conversion is 2,544 BTU/hr per mechanical HP. The first is what appliances are sold on.

Around 500 BTU/hr per m² for a residential room with a 2.7 m ceiling and moderate sun. High heat-gain rooms need more.

About 11,900 BTU/hr — just under 1 ton, sold as a 1.5 HP unit, suiting roughly 24 m² under average conditions.

No. Cooling kW is heat removed; electrical kW is power drawn, typically three to four times smaller because an air conditioner moves heat rather than creating it.