Avoid buying an undersized or oversized air conditioner with our AC BTU Calculator. Enter your room dimensions, ceiling height, insulation quality, and sunlight exposure to get an accurate recommendation for BTUs and cooling tonnage. Proper sizing ensures energy efficiency and comfort.
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Calculate AC Size & BTU Needs
Determine the correct air conditioner size for your room. Convert room dimensions to required BTUs and Tonnage. Fast, free, and 100% private browser tool.
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1
Room Dimensions
Enter length, width, and ceiling height.
2
Adjust Factors
Select sunlight exposure and insulation quality.
3
Occupancy
Add number of people and check if it's a kitchen.
Key Features
Precise BTU Calculation
Accounts for room size, ceiling height, and occupancy.
Environmental Factors
Adjusts for sunlight exposure, insulation quality, and kitchen heat.
Tonnage Conversion
Instantly converts BTUs to standard AC tonnage.
Frequently Asked Questions
A general rule of thumb is 20-25 BTUs per square foot for a standard room with 8-foot ceilings.
One ton of cooling capacity equals 12,000 BTUs per hour. It represents the amount of heat required to melt one ton of ice in 24 hours.
An oversized AC will cool the room too quickly without dehumidifying it properly, leading to a clammy feeling and frequent short cycling.
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