BTU Cooling Load Calculator
Estimate air conditioner size in BTU/h, kW and tons for a room.
Inputs
m²
m
people
Results
- Cooling load
- ≈ 5,735 BTU/h
- Cooling capacity
- ≈ 1.68 kW
- Cooling capacity
- ≈ 0.48 tons
Formula
Base = ft² × 20 BTU/h × (ceiling ÷ 2.44 m)
× 0.9 shaded / 1.1 sunny; + 600 per person over 2; + 4000 for kitchens
Assumptions & limits
- Residential rule of thumb (ENERGY STAR style). Commercial spaces need a proper heat-load calculation.
Worked example
25 m² = 269.1 ft² × 20 × 1.066 ≈ 5,735 BTU/h ≈ 1.68 kW.