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AC Tonnage Calculator.
Convert a stated cooling load from BTU per hour to refrigeration tons.
Set your values
Results update as you type.
Results use only the stated formula and entered units; they are not building-code, equipment-sizing, or structural design advice.
Use Cases
Sizing Air Conditioners
When you have a heat load calculation in BTU/h, use this tool to express it in tons, which is a common unit for AC capacity.
Example: A room with a heat load of 36,000 BTU/h equals 3 tons.
Comparing Equipment Ratings
Convert manufacturer specs from BTU/h to tons to compare different AC units on the same scale.
Example: An AC rated at 18,000 BTU/h is 1.5 tons.
Frequently Asked Questions
- How do I use the AC Tonnage Calculator?
- Simply enter your heat load in BTU per hour (BTU/h) into the 'Heat load' field. The calculator will convert it to refrigeration tons, where 1 ton equals 12,000 BTU/h.
- What is a refrigeration ton?
- A refrigeration ton is a unit of cooling capacity. One ton equals the amount of heat required to melt one ton of ice in 24 hours, which is 12,000 BTU per hour.
- Why is my result in tons and not kW?
- This calculator specifically converts BTU/h to refrigeration tons. If you need kilowatts, you would need a different conversion tool.
Tips & Common Mistakes
Tips
- Ensure your heat load is in BTU per hour (BTU/h) before entering it.
- Remember that 1 ton equals 12,000 BTU/h, so you can also divide by 12,000 manually.
- This calculator is for converting a known heat load; it does not calculate the heat load itself.
- For residential sizing, typical capacities range from 1 to 5 tons.
Common Mistakes to Avoid
- Entering heat load in BTU per minute or per day instead of per hour.
- Confusing refrigeration tons with weight tons; they are different units.
- Using the result as a final AC size without considering other factors like insulation or climate.
Last updated: August 13, 2026