
HVAC Duct Sizer Pro
Offline ductulator for HVAC
0 ratings
$1.99
Rating summary
About
Size a duct in seconds — on site, with no signal needed.
HVAC Duct Sizer Pro is a digital ductulator for mechanical engineers, designers and field technicians. Enter an airflow and a design criterion, and the duct size appears instantly, computed from ASHRAE Fundamentals duct-design methods.
SIZE MODE
• Enter airflow plus either a friction rate or a target velocity
• Exact round diameter, plus the nearest standard size (EN 1506 and imperial)
• Rectangular equivalent — give one side, get the other (Huebscher)
• Actual velocity, friction rate, velocity pressure and Reynolds number
ANALYZE MODE
• Enter airflow and an existing duct — round diameter or rectangular a×b
• Instantly see velocity, friction rate, velocity pressure and Reynolds number
• Check an existing run against design limits before you order material
REAL ENGINEERING, NOT A LOOKUP TABLE
• Colebrook–White friction factor, solved iteratively — not a chart approximation
• Duct material roughness: smooth, galvanized steel, lined, flex, rough
• Standard air, or your own custom density
• Hints for typical design ranges, and warnings for high aspect ratio or laminar flow
UNITS THAT FIT YOUR OFFICE
• SI and IP throughout
• Airflow in L/s, m³/h or CFM, chosen independently
WORKS ANYWHERE
• 100% offline — no account, no sign-up, no internet connection
• No ads, no subscription, no tracking, no data collection
• One single purchase, yours for good
Available in English, Japanese, Simplified Chinese, Korean, French, German, Spanish and Vietnamese.
From the developer of AirCalc Pro.
Show more
What's New in HVAC Duct Sizer Pro
1.2.0
September 12, 2026
The app now speaks your language. • Added Japanese, Simplified Chinese, Korean, French, German, Spanish and Vietnamese • The app picks up your device language automatically on first launch • Devices set to a United States region now start in IP units
More




