Everyday Converters
BTU Calculator
Estimate heating or cooling BTU needs from room area and BTU per square foot.
Result
--What does this calculator do?
Estimate heating or cooling BTU needs from room area and BTU per square foot.
Formula
BTU estimate = room area × BTU per square foot.
Example calculation
300 sq ft at 25 BTU/sq ft suggests about 7,500 BTU.
Common use cases
- Room AC sizing
- Heating estimates
- HVAC planning
Limitations and accuracy notes
This calculator is for quick planning and education. Results depend on your inputs and may not include every real-world rule, fee, tax, health factor, local requirement, or professional standard.
BTU Calculator FAQ
Is this calculator free?
Yes. It gives quick estimates directly in your browser.
Should I use this as professional advice?
No. Use it as a planning aid and confirm important decisions with a qualified professional.