Room BTU Calculator
A common planning figure is about 20 BTU per square foot of living space for cooling, then adjust for sun, kitchen heat, and ceiling height. This is not a Manual J load calculation. HVAC sizing should be done by a professional.
Estimated BTU/h5,000
Tons (approx.)0.421 ton ≈ 12,000 BTU/h
Rule of thumb only — not an HVAC design.
Formula
BTU/h ≈ area × 20 × sun factor.
How to use this calculator
- Enter room square footage.
- Adjust for sun.
- Treat the result as a starting range only.
Examples
250 sq ft average sun
About 5,000 BTU/h.
FAQ
Is bigger better?+
Oversized AC can short-cycle and dehumidify poorly. Get a proper load calc.
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