Energy
Convert air-conditioner cooling capacity between BTU per hour, refrigeration tons, and watts.
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AC cooling capacity converter guide
Air conditioners are labelled three different ways depending on where you shop: BTU per hour in North America, refrigeration tons across South Asia and the Middle East, and watts or kilowatts of cooling on European and Japanese datasheets. This converter moves a rated cooling capacity between those three units so you can compare a “1.5 ton” split unit with an “18,000 BTU” window unit or a “5.2 kW” inverter model and see they are the same class of machine. Enter the capacity, pick the unit it is quoted in, and choose the unit you want. The result is cooling output, not electrical input: a 12,000 BTU/h unit removes about 3.5 kW of heat but may draw only 1 to 1.5 kW of electricity depending on its EER or ISEER rating. Use the running-cost calculator for the electricity side, and use this page when you are matching a unit to a room, a quote, or a generator or inverter that must start it.
BTU/h = tons × 12,000. Watts (cooling) = BTU/h ÷ 3.412141633. Tons = BTU/h ÷ 12,000. The converter first expresses the input in BTU/h, then divides by the factor for the target unit.
Worked example: convert 12,000 BTU/h to tons. The input is already in the base unit, so 12,000 ÷ 12,000 = 1 ton. The side rows show the same capacity in every unit: 12,000 BTU/h; 12,000 ÷ 3.412141633 = 3,516.85 W of cooling. Going the other way, a 1.5 ton split unit is 1.5 × 12,000 = 18,000 BTU/h, or 18,000 ÷ 3.412 = 5,275 W (about 5.3 kW). The calculator displays 1 ton for the default inputs.
The “From” and “To” fields accept BTU/h, refrigeration tons, and watts. Tons here are refrigeration tons (12,000 BTU/h each), not mass. Watts are watts of cooling capacity, not the compressor’s electrical draw. If a datasheet quotes kilowatts, multiply by 1,000 before entering; if it quotes kcal/h, multiply by 3.968 to get BTU/h first. Horsepower ratings (common in the Philippines and Japan) are roughly 9,000 to 9,500 BTU/h per HP but vary by brand, so use the BTU or kW figure on the label instead.
This is a modelled estimate, not a meter reading. Real consumption moves with weather, occupancy, appliance age, standing charges, and tariff structure, and equipment rarely runs at its nameplate rating. Use the figure to compare options against each other, then confirm against your own bill and the manufacturer's specification before committing to a purchase. On this page the figure rests entirely on capacity, from, to, market / jurisdiction, effective date, data source, update owner and review date, so start there if the ac cooling capacity converter returns something you did not expect.
Good to know: the most common slip is treating cooling watts as electrical watts and then sizing a generator or inverter far too large. A 1 ton unit delivers about 3,517 W of cooling but typically draws 900 to 1,300 W running, plus a starting surge for non-inverter compressors. The reverse mistake is assuming “12,000 BTU” means energy: the label means BTU per hour, a rate. Finally, do not round 1.5 tons to “about 1 ton” when checking room size; the half ton is roughly 6,000 BTU/h, enough for another 10 to 14 m².
Energy results depend on tariffs, equipment behavior, region, weather, and installation assumptions. Verify rates and electrical decisions with the utility, manufacturer, or qualified professional.
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How it works
Convert air-conditioner cooling capacity between BTU per hour, refrigeration tons, and watts. This tool explains the calculation so you can adjust the assumptions to match your situation.
Worked example
With Capacity = 12000 BTU/h · From = BTU/h · To = tons → 1 tons (12,000 BTU/h converted to tons). Change an input above and this example updates with your numbers.
Common questions
A 1.5 ton air conditioner is rated at 1.5 × 12,000 = 18,000 BTU/h, which is about 5,275 W (5.3 kW) of cooling. This is the most common size for a 14 to 18 m² bedroom in hot climates such as Bangladesh and India.
12,000 BTU/h equals 12,000 ÷ 3.412 = about 3,517 W of cooling capacity, which is exactly one refrigeration ton. The electrical input is lower, typically 1,000 to 1,300 W for a modern 1 ton split unit.
No. A refrigeration ton is the rate of heat removal needed to melt one short ton of ice in 24 hours, standardised at 12,000 BTU/h or about 3.517 kW. It says nothing about the unit’s physical weight.
Divide BTU/h by 3,412 to get kilowatts of cooling. For example, 24,000 BTU/h ÷ 3,412 = 7.03 kW, the capacity of a 2 ton unit. Enter the BTU figure above and choose watts to see the exact value.
Convert the cooling rating to electrical draw first: a 1 ton unit usually needs 1 to 1.3 kW running and, for fixed-speed compressors, up to 3 kW for a second or two at start-up. Inverter-type ACs soft-start and are far easier on backup systems.