Our main product is our load calculation software, but we also build a handful of free tools for everyday HVAC work.
Calculate psychrometric properties of air: humidity, enthalpy, dewpoint and more. Built for engineers and technicians working with air-conditioning systems.
Open calculatorApply fan and pump affinity laws to find changes in airflow, static pressure and power when varying speed. Useful for system balancing and energy analysis.
Open calculatorCalculate pipe pressure drop, flow rates and fluid temperatures for hot- and chilled-water systems. Handy for design and troubleshooting.
Open calculatorSize rectangular and round ducts by calculating airflow, velocity and pressure drop, a go-to tool for duct sizing in HVAC design.
Open calculatorBuild a duct-run schedule with round, rectangular and flat oval sections, fittings and changing airflow. Get total system pressure loss and fan power, with altitude and temperature corrections.
Open calculatorCalculate friction and valve/fitting head loss for closed-loop hydronic systems with water or glycol. Get total head loss and pump power for each piping schedule.
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