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About BTU Calculator

The BTU (British Thermal Unit) Calculator helps select the right size Air Conditioner or Space Heater.

Why Size Matters?

  • Too Small: Won't cool/heat the space; runs continuously.
  • Too Big: Cycles on/off too fast (short cycling), failing to dehumidify the air.

General Rules

A baseline for standard rooms is approx 20-25 BTUs per square foot. Factors like high ceilings, sun exposure, and kitchen appliances add load.

How to Use

Enter room dimensions. The tool provides a BTU range suitable for window AC units or mini-splits.