Free tool
Which size AC does your room need?
Enter the room size and how sunny it is. The answer updates as you type.
Suggested AC size
0.75 ton
144 sq ft · about 3,600 BTU/hr (0.30 ton)
Choose a 5-star inverter AC of this size for lower bills. Rounded up slightly so the room stays cool on 44 °C days.
How it works
How is the AC size worked out?
About 25 BTU/hr per square foot for a room with a 10 ft ceiling in a hot summer, 15–30% more for a top floor or west-facing wall, plus about 600 BTU/hr for every extra person and the heat from equipment. One ton of cooling is 12,000 BTU/hr.
What happens if the AC is too small?
It runs at full power all day, cools slowly on hot afternoons and uses more electricity. A slightly bigger inverter AC usually costs less to run.
Is this enough for an office, hall or shop?
For one room, yes. For several rooms, glass fronts, kitchens or halls, ask for a free site survey: we measure the load properly and may suggest a cassette, ductable or VRV system.