Estimate the cooling BTU capacity needed for a room
Our BTU Calculator estimates the cooling capacity (in British Thermal Units per hour) needed to effectively cool a room. It accounts for room dimensions, insulation quality, sun exposure, climate zone, number of windows, and typical occupancy. Proper BTU sizing ensures efficient cooling without over- or under-sizing your air conditioner.
An undersized AC runs continuously without reaching the set temperature. An oversized AC short-cycles, leading to poor humidity control and higher energy bills.
An oversized unit will cool the room quickly but won't run long enough to remove humidity, leaving the space feeling clammy and cold. It also cycles on and off frequently, which increases wear and energy consumption.
BTU ratings apply to both heating and cooling, but heating calculations differ because they must account for heat loss through walls, windows, and ceilings. For heating, consider climate-specific factors like outdoor design temperature and building envelope efficiency.