🧰 Built by a technician

HVAC Tools & Calculators

Practical calculators I use on the job — free for homeowners, DIYers, and fellow techs. More tools added regularly.

Every essential HVAC tool compared across Budget, Mid-Range, and Pro brands in one interactive table.

Estimate the BTUs you need to heat or cool a room — adjusted for climate, sun, and ceiling height.

Calculate system superheat from your suction line and saturation temperatures.

Calculate subcooling from your liquid line and liquid saturation temperatures.

Check your system’s temperature split across the evaporator coil.

Estimate total external static pressure for your ductwork.

Estimate what a unit costs to run based on efficiency and local energy rates.