HVAC BTU Calculator
Estimate basic heating or cooling capacity by room size.
Estimate
How to use this calculator
Enter your measurements, product coverage and pricing where requested. Results update instantly as values change.
Formula
Basic capacity uses floor area, ceiling-height and climate adjustments.
Planning tip
This is a rough sizing estimate only. A professional Manual J load calculation accounts for insulation, windows, orientation and air leakage.
Frequently asked question
Should I round up?
Yes. Round purchase quantities up to whole packages, rolls, pieces or containers and verify coverage with the product manufacturer.