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AC Tonnage Calculator

Air conditioner tonnage for a room, with the BTU rating and estimated running cost.

Enter values

Results update as you type.

Result

Recommended tonnage

0.75 tons

Calculated requirement
0.725 tons
BTU rating
8,700 BTU/h
Power draw
0.818 kW
Daily energy
6.55 kWh
Daily running cost
$1.64
Monthly running cost
$49.09

About the AC Tonnage Calculator

Air conditioner tonnage for a room, with the BTU rating and estimated running cost.

Also known as: ac size calculator, how many tons ac, air conditioner tonnage for room, split ac size.

How to use this calculator

  1. Enter room area, ceiling height, climate, occupants and the other fields.
  2. The result updates instantly as you type — press Calculate (or Enter) at any time.
  3. Review the breakdown shown under the main result.
  4. Use Copy result or Share to save the answer or send a link with your inputs.

Formula

1 ton of cooling = 12,000 BTU/h

Worked example

Using the values pre-filled in the calculator above:

  • Room area = 20 m²
  • Ceiling height = 2.5 m
  • Climate: Moderate
  • Occupants = 2
  • Hours of use per day = 8
  • Electricity rate per kWh = 0.25
  • Efficiency (EER) = 11

the calculator returns:

  • Recommended tonnage: 0.75 tons
  • Calculated requirement: 0.725 tons
  • BTU rating: 8,700 BTU/h
  • Power draw: 0.818 kW