Air Conditioner BTU Calculator | Room Cooling Size
Estimate recommended air conditioner BTU/h from room area, ceiling height, sun exposure adjustment, and number of occupants.
Recommended Cooling Capacity
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Estimate Air Conditioner BTU for a Room
Enter room area, ceiling height, sun exposure adjustment, and occupant count to estimate cooling capacity in BTU/h, tons, and watts.
Room Conditions Affect Cooling Needs
Insulation, window size, afternoon sun, appliances, climate, door openings, and room layout can change the recommended BTU. Use the result as a sizing estimate.
About This Tool
Air Conditioner BTU Calculator estimates the cooling capacity needed for a room based on floor area, ceiling height, sun exposure, and insulation. Choosing the right BTU rating prevents under-cooling and wasted energy from oversized units.
When to Use It
Use this before buying a window unit or portable air conditioner to avoid purchasing one that is too weak or so large it cycles inefficiently.
How to Use
- Enter the room length and width in metres or feet.
- Set the ceiling height and sun exposure level.
- Indicate whether the room is well-insulated.
- Click Calculate to see the recommended BTU range.
Frequently Asked Questions
What is a BTU?
BTU stands for British Thermal Unit. In air conditioning it measures how much heat a unit can remove per hour. A higher BTU rating means more cooling power.
Is a bigger AC unit always better?
No. An oversized unit cools too quickly without removing enough humidity, leaving the air cold but clammy. Right-sizing is important for comfort and efficiency.
Should I add extra BTUs for a kitchen?
Yes. Kitchens generate significant heat. Add roughly 4 000 BTU to the calculated result for rooms that include a cooking area.