Digiduct vs DuctPro
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
Digiduct
This HVAC tool assists professionals with duct sizing calculations based on ASHRAE standards. It supports multiple duct shapes and offers intelligent features to ensure accurate and reliable designs for real-world scenarios.
- Duct sizing for rectangular, round, and flat oval ducts
- Customizable dimensions with locked values
- Duct location intelligence for context-aware sizing
- Calculations based on CFM, pressure drop, or velocity
- Alerts for exceeding pressure drop or velocity limits
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The Digiduct app is a powerful tool designed for HVAC professionals, supporting everything from design calculations to real-time field verification. Built utilizing the equations and recommendations from the ASHRAE Fundamentals – Duct Design chapter, it ensures your calculations are accurate and reliable, saving you time and reducing errors. Key Features: • Multiple Shape Sizing Options: Supports sizing for rectangular, round, and flat oval ducts, offering flexibility for various duct designs. • Customizable Dimensions: For rectangular and oval ducts, users can lock in one dimension, and the app calculates the other, ensuring precise results based on CFM, pressure drop due to friction, or velocity. • Duct Location Intelligence: offers the user predefined parameters to use as starting point and reference when selecting duct sizes so users at HVAC experience level can make confident selections. Why Choose Digiduct? Unlike other duct sizing tools, Digiduct goes above and beyond. It doesn’t just provide basic size outputs—it evaluates the location and context of your duct (high-pressure vs. low-pressure, shaft vs. plenum), alerting you if your selection exceeds maximum pressure drop or velocity limits. This added layer of intelligence ensures higher accuracy and gives users confidence that their sizing is optimal for the application. Get the assurance of precision with Digiduct—designed to meet the demands of real-world HVAC scenarios.
DuctPro
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DuctPro is the professional HVAC duct sizing calculator built for field technicians and MEP engineers. Get engineering-grade results in seconds — offline, no subscription. RESULTS IN 3 TAPS Enter airflow, select duct type, get the size. Round, rectangular, flat oval, and flexible ducts. Size by friction rate or air velocity. A color-coded performance badge tells you instantly if your duct is optimal, too fast, too slow, or at risk. ENGINEERING-GRADE ENGINE Calculations use the Darcy-Weisbach friction equation with Colebrook-White solver — the industry-standard method for duct design. Nine material types with published roughness values: galvanized steel (spiral & rectangular), flexible duct (metallic & non-metallic), fiberglass duct board, fibrous glass liner, PVC, aluminum, and concrete. FITTINGS & PRESSURE DROP Calculate total system pressure drop including straight run and all fittings. Ten fitting types with industry-standard loss coefficients: 90° and 45° elbows (round and rectangular), mitered elbow, tee branch and straight-through, concentric reduction, enlargement, and butterfly damper. PRO MODE Unlock full 2D lookup tables for rectangular elbows and concentric reductions, plus A/B ratio selector for flat oval ducts. Bilinear interpolation for accurate results at any H/W or area-ratio geometry. ORGANIZE YOUR WORK Save calculations with a custom name and notes. Group them into color-coded projects. Export individual calculations as text or PDF, and full projects as CSV. Search your entire history in one tap. IMPERIAL & METRIC Switch between I-P and SI units at any time. All inputs and outputs update instantly across every screen. I-P: CFM · in · ft/min · inWC/100ft SI: L/s · mm · m/s · Pa/m 6 LANGUAGES English · Français · Español · Português · Deutsch · Italiano — 100% offline. No account. No subscription. —
Screenshots
Verdict
The clearest difference is update cadence: DuctPro at weekly against Digiduct's every 2 months. DuctPro also leads on iOS requirement (17.0 vs 26.2). On price, ads, in-app purchases and device support there is nothing between them.
Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS
Both are free to download. Neither carries in-app purchases, so what you see is what you pay.
Digiduct ships an update every 2 months, DuctPro weekly. The most recent releases landed on October 1, 2026 and September 19, 2026 respectively.
| Parameter | Digiduct | DuctPro |
|---|---|---|
| Price | Free | Free |
| Rating | 4.6 (11 ratings) — better | — |
| Number of ratings | 11 — better | — |
| Update frequency | Every 2 months | Weekly — better |
| Ads | No | No |
| In-app purchases | No | No |
| Monetization | Ad-supported | — |
| Devices | iPhone, iPad | iPhone, iPad |
| Requires iOS | 26.2 | 17.0 — better |
| Further details — not scored | ||
| Size | 4 MB | 3 MB |
| Age rating | 4+ | 4+ |
| Developer | Syska Hennessy Group | High Intent Labs |
In-app purchases
Digiduct
No in-app purchases
DuctPro
No in-app purchases








