Calculator
AC Tonnage Calculator
Convert BTU per hour to cooling tons and thermal kW without treating the result as central HVAC sizing.
What is included
- • Visible formula and assumptions
- • Browser-side instant result
- • Result range instead of pseudo-precision
- • Copy result, share URL, CSV export and print/PDF
- • Source notes and professional boundary
What is not included
- • Whole-home Manual J/S/D design
- • Local code compliance
- • Health or mold remediation guarantee
- • Electrical, refrigerant, gas or combustion safety
- • Product installation approval
Sources and maintained assumptions
Sizing assumptions are centralized and show source URLs, check dates and notes.
- DOE Room Air Conditioners
Checked 2026-05-22. Used for room AC preliminary BTU rule, room-level sizing caveats and oversizing humidity cautions.
- DOE Portable Air Conditioners Test Procedure
Checked 2026-05-22. Used for portable AC SACC / label caveats.
- ENERGY STAR Certified Dehumidifiers
Checked 2026-05-22. Used for pints/day and product rating caveats.
- HVI Bathroom Ventilation
Checked 2026-05-22. Used for residential bathroom fan CFM rules and fixture model.
- ACCA Technical Manuals
Checked 2026-05-22. Used to define Manual J, Manual S and Manual D boundaries.
- EPA Mold and Indoor Air Guidance
Checked 2026-05-22. Used for mold and water intrusion disclaimers.
FAQ
Is this a professional HVAC design?
No. It is a room-level preliminary estimate and does not replace Manual J, Manual S, Manual D, product manuals, local code, or qualified professionals.
Why does the calculator show a range?
Room conditions vary by climate, windows, insulation, air leakage, installation, product labels and moisture sources, so a range is more honest than a pseudo-exact number.