HVAC Duct Sizer Pro
Offline ductulator for HVAC
Only for iPhone
$1.99 · Designed for iPhone. Not verified for macOS.
iPhone
A digital ductulator that works with no signal. Airflow in, duct size out. ASHRAE methods, SI and IP, no ads and no subscription.
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.
Ratings & Reviews
- This app hasn’t received enough ratings or reviews to display an overview.
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
The developer, Duong Nguyen Huu, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Not Collected
The developer does not collect any data from this app.
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Seller
- Duong Nguyen Huu
- Size
- 31.8 MB
- Category
- Utilities
- Compatibility
Requires iOS 16.4 or later.
- iPhone
Requires iOS 16.4 or later. - Mac
Requires macOS 12.0 or later and a Mac with Apple M1 chip or later. - Apple Vision
Requires visionOS 1.0 or later.
- iPhone
- Languages
English and 7 more
- English, French, German, Japanese, Korean, Simplified Chinese, Spanish, Vietnamese
- Age Rating
4+
- 4+
- Copyright
- © 2026 Gnouden
