Air Conditioner Sizing Calculator
BTUs and tons for cooling a space.
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How to use this calculator
- Enter the area you want to cool.
- See BTUs and tonnage needed.
- Add capacity for sunny or high-ceiling rooms.
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Frequently asked questions
- What size air conditioner do I need?
- Plan about 20 BTU per square foot. A 600 sq ft space needs roughly 12,000 BTU, or one ton of cooling.
- What is a ton of air conditioning?
- One ton of cooling equals 12,000 BTU per hour. Central AC units are commonly 1.5 to 5 tons.