BTU Calculator
Calculate the BTU needed to heat or cool a room. Size your air conditioner or heater correctly for maximum efficiency.
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Calculator insights
What this calculator does
BTU Calculator helps you quickly estimate calculate the btu needed to heat or cool a room. size your air conditioner or heater correctly for maximum efficiency. with clean output and clear next steps.
How the calculation works
Enter Room Length, Room Width, Ceiling Height and this calculator uses standard formulas to determine Required BTU/hr and AC Tonnage. The output is displayed immediately in a user-friendly format.
Example calculation
For example, enter realistic values into the BTU Calculator to see how the calculator produces Required BTU/hr and AC Tonnage that you can use for planning and comparison.
Disclaimer
The calculations provided by this website are for informational purposes only and should not be considered financial, legal, tax, or professional advice.
Frequently Asked Questions
How do I size an air conditioner?
General rule: 20 BTU per sq ft. A 300 sq ft room needs ~6,000 BTU (0.5 ton). Add 10% for sunny rooms, subtract 10% for heavily shaded rooms.