HVAC CALCULATOR

HVAC size calculator

Get a preliminary cooling-capacity range from a few planning inputs. A professional load calculation is still required before equipment selection.

Starting point: typical planning conditions. Adjust each input to better match your home.

Home size (sq ft) Enter a home size from 100 to 20,000 sq ft.

Climate Choose the climate that best describes your location.

Insulation Estimate the condition of the home's insulation.

Ceiling height (ft) Enter an average ceiling height from 7 to 20 ft.

Sun exposure Estimate how much direct sun reaches the home.

Window exposure Estimate the home's window exposure and solar load.

Method: preliminary planning estimate using 20 BTU/sq ft, adjusted for the selected climate, insulation, ceiling height, sun exposure, and windows. Results are rounded to 6,000 BTU/h (0.5 ton) planning steps and never display below 6,000 BTU/h. Confidence: D (derived). This is not a Manual J load calculation. Last reviewed: 2026-08-29.