AC Tonnage Calculator Dubai
This calculator sizes an air conditioner for a Dubai room from its floor area and sun exposure. It works out the cooling load in BTU using a Dubai-appropriate rule of about 45 BTU per square foot, adjusts for orientation and floor, and converts to tons, so you can specify a unit that actually keeps the room comfortable through a Dubai summer without wasting energy.
AC Tonnage & Cooling Load Calculator
An undersized air conditioner never cools; an oversized one wastes power. As a Dubai
rule of thumb, a room needs roughly 40 to 45 watts of cooling per square foot. Set your room size to get the
approximate BTU and ton rating you need.
How it's calculated
BTU = floor area in square feet times 45, times a sun factor (1 normal, 1.1 sunny, 1.2 very hot). Tons = BTU divided by 12,000. Example: a 12 by 15 foot room is 180 square feet, times 45 is 8,100 BTU, about 0.7 ton.
Indicative only. A site survey confirms the exact load.
Need it supplied and fitted? See AC installation & maintenance.
What size AC do I need for a Dubai room?
Size is driven by cooling load, not just floor area. As a working rule for Dubai's climate, a room needs roughly 45 BTU per hour per square foot, more if it faces the afternoon sun, sits under a hot roof, has large windows or a lot of glass. The calculator applies that rate, adjusts for exposure, and divides by 12,000 to give the size in tons, since one ton of cooling equals 12,000 BTU per hour.
Why oversizing an AC is a mistake
An oversized unit cools the air quickly but short-cycles: it hits temperature and shuts off before it has pulled the humidity out, so the room feels cold and clammy, the compressor wears from frequent starts, and efficiency drops. In Dubai's humidity, correct sizing matters as much for comfort as for the electricity bill. Bigger is not better.
Why undersizing is worse in summer
An undersized unit runs flat out on the hottest days and never quite reaches temperature, so it costs more to run for less comfort and fails exactly when you need it. The goal is a unit matched to the real load, which is what this calculator estimates.
What changes the real number
Ceiling height, insulation quality, the number of occupants, heat from kitchens and equipment, and how airtight the room is all move the load. Treat the result as a sound starting point for specifying a unit; a site survey confirms it against the real room. For a whole villa, the loads add up and the electrical supply has to carry them, which is a separate check.
Sizing or replacing cooling across a home? See AC maintenance and servicing or HVAC and air quality.
