Air Conditioner BTU Calculator

Find the cooling capacity in BTU/h for a room.

Cooling needed (BTU/h) 8,000
AC size (tons) 0.6667

Formula: BTU = area × BTU/ft²

Step-by-step with your numbers:
1. Values used:
2. Room area = 400
3. BTU per ft² = 20
4.
5. Cooling needed = Room area x BTU per ft² = 400 x 20 = 8,000BTU/h
6. AC size = 0.6667tons
Did we solve your problem today?

Estimate air conditioner size in BTU and tons.

The math behind it

BTU/h = area × ~20 BTU/ft²; 1 ton = 12,000 BTU/h.

Worked example

400 ft² → 8,000 BTU.

FAQ

Windows/insolation?

Add extra capacity for large windows and sun exposure.