DuctCFMCalculator.com is a specialized HVAC utility built to modernize the way technicians and contractors size ductwork. We know that carrying around a physical “ductulator” slide rule is outdated, and spreadsheets are clumsy on a mobile screen.
We built this tool to be the ultimate job-site companion. Unlike basic calculators, our engine accounts for real-world variables like Friction Loss in Flex Duct (derating airflow by 15%), Shape Geometry (Round vs. Rectangular vs. Flat Oval), and Velocity Limits for residential vs. commercial noise levels. Whether you are balancing a home system or designing a commercial trunk line, we provide the precision math you need to ensure optimal system performance.
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