# Duct Mate: HVAC Duct Sizer — Duct Sizing & Airflow Calc > Duct Sizing & Airflow Calc (iPhone/iPad app by 彧 殷.) - Source: https://appshunter.io/ios/app/duct-mate-hvac-duct-sizer/id6769504373 (this page in markdown: same URL + `.md`) - Developer: [彧 殷](https://appshunter.io/developer/1857113787) - Category: Utilities, Productivity - Price: Free with in-app purchases - Age rating: 4+ - Requires: iOS 26.2 · 2 MB - Languages: American English - Released: 2026-06-30 - Data updated: 2026-07-02 - User reviews in markdown: https://appshunter.io/ios/app/duct-mate-hvac-duct-sizer/id6769504373/reviews.md ## What is Duct Mate? Duct Mate is the HVAC duct sizing tool built for the field — fast, offline, and transparent. Size ducts by CFM, analyze existing runs, find equivalent sizes, and calculate design friction rate from static pressure — all without creating an account or connecting to the internet. CORE TOOLS — ALL IN ONE APP ▸ Duct Size by Airflow Enter CFM, choose supply/return/exhaust, pick a shape and material, tap "Size" — get a recommended duct size instantly. Switch between friction and velocity methods. Supports round, rectangular, flex, and flat oval ducts with galvanized metal, flex duct, and duct board materials. ▸ Existing Duct Analyzer Got a duct that's already installed? Enter its size to find out how much CFM it can actually handle (Capacity Solver mode), or check what velocity and friction you're getting at a given airflow (Diagnostic mode). This is the reverse-sizing feature field techs have been asking for. ▸ Equivalent Duct Calculator Convert round to rectangular, rectangular to round, round to flat oval — every equivalent size shows cross-sectional area, equivalent diameter, and velocity change. Perfect for material swaps and retrofit work. ▸ Friction Rate Helper Calculate design friction rate the Manual D way: enter external static pressure, subtract component pressure losses (coil, filter, registers, grilles), divide by total equivalent length (supply + return). Built-in TEL calculator: simply tap a straight duct run, select fittings (14 types in the library), add equivalent length — no manual lookup tables needed. One tap to apply your friction rate back to the duct sizer. DESIGNED FOR THE FIELD • Works completely offline — no internet, no account needed • US (IP) and SI (metric) units with one-tap switching • Keyboard input, no cumbersome sliders • Quick-pick buttons for common CFM values and friction rates • Every result shows the formula, assumptions, and warnings • Save jobs, pin favorites, share results as text PRO FEATURES — ONE-TIME PURCHASE Unlock everything with a single purchase. No subscriptions. FREE —————————————— PRO ($4.99, one-time) Round, rectangular, flex ——— + Flat oval Return Air Helper ————————— + Return Air recommendations Room Split Calculator ———— + Room CFM planning 3 candidate sizes —————————— 18 candidate sizes 3 saved calculations ——————— Unlimited saves Text sharing ———————————————— + CSV & PDF export Standard settings —————————— + Advanced settings Friction Rate Helper —————— + Fitting Equivalent Length library TRANSPARENT, NOT A BLACK BOX Duct Mate is not a replacement for ACCA Manual D, but it's built to support Manual D workflows. Every calculation displays: • The underlying formula and assumptions • Standard air density (0.075 lb/ft³) • Material roughness and friction factor • Velocity limits with warnings when exceeded • Aspect ratio cautions for rectangular ducts • A clear disclaimer for professional verification TRUSTED BY HVAC PROS No subscription. No account. No data collection. Works offline wherever the job takes you. Download Duct Mate today — the duct sizer that works the way you do. ## Pricing and in-app purchases Base price: Free. **One-time purchases** | Purchase | Price | Type | | --- | --- | --- | | DuctWise Pro | $4.99 | one-time | ## Version history (last 1 release) ### 1.0 — 2026-06-30 No release notes. ## More apps by 彧 殷 - [实况工坊 - Live Photo 壁纸与拼接](https://appshunter.io/ios/app/live-photo/id6755945191) - [Conduit Mate: Pipe Bender](https://appshunter.io/ios/app/conduit-mate-pipe-bender/id6757356982) - [PrivaPic: EXIF & GPS Cleaner](https://appshunter.io/ios/app/privapic-exif-and-gps-cleaner/id6758293167) All apps by 彧 殷: https://appshunter.io/developer/1857113787 --- *Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-07-02.*