Duct Calculator vs Dairy Ventilation
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
Duct Calculator
This professional HVAC utility assists engineers and technicians with precise duct sizing and airflow calculations for ventilation systems. It simplifies essential calculations for both design and installation work, improving on-site efficiency.
- Calculate duct sizes using airflow (CFM) and velocity (FPM)
- Supports rectangular and round duct sizing in inches
- Determine air flow rate in CFM
- Calculate air velocity in FPM
- Simple interface for fast on-site calculations
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Duct Calculator is a focused duct sizing tool for HVAC engineers, designers and installation technicians. Enter what you know and get the duct dimensions, airflow or air velocity you need, without a chart or a slide rule. CALCULATIONS - Duct size: find the required duct dimensions from airflow (CFM) and air velocity (FPM). - Airflow: determine the airflow rate in CFM. - Air velocity: determine velocity in FPM to help verify system performance. DUCT SHAPES - Round ducts - Rectangular ducts - Results shown in inches WHO IT IS FOR - HVAC engineers and designers checking a duct size during design work. - Installation technicians and contractors who need a quick answer on site. - Students learning how airflow, velocity and duct size relate. WHERE IT HELPS - Sizing a new supply or return run from a known CFM. - Checking whether an existing duct keeps velocity within your target. - Comparing a round duct with a rectangular one when space is tight. SIMPLE BY DESIGN A clean interface with only the inputs you need, so you get an answer quickly on the job. Duct Calculator is free to use. An optional one-time upgrade removes ads. Results are intended as a calculation aid. Always confirm designs against applicable codes and project requirements. Download Duct Calculator and size your next duct run. Privacy Policy : https://semiconhub.in/manager/privacy.html Terms and Condition : https://semiconhub.in/manager/tcondition.html
Dairy Ventilation
This tool helps dairy producers make informed decisions about managing heat stress and mechanical ventilation in barns. It calculates key metrics like the Temperature-Humidity Index and fan efficiency, aiding in system design and upgrades.
- Temperature-Humidity Index (THI) calculation with location-based weather
- Fan sizing and selection for barns
- Assessment of existing ventilation performance
- Fan efficiency comparison
- Payback period analysis for upgrades
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Welcome to the Dairy Ventilation Calculator- a free UW-Madison Extension tool for dairy producers to support decisions about heat stress management and mechanical ventilation in dairy barns. FEATURES - THI (Temperature-Humidity Index) with location-based weather - Adopting Fans calculator — size and select fans for your barn - Evaluating Ventilation calculator — assess existing ventilation performance - Fan Efficiency comparison chart — compare fan models side by side - Payback Period analysis — estimate return on investment for upgrades WHO IT'S FOR - Dairy producers managing heat stress in cow housing - Farm managers planning fan upgrades or new ventilation systems - Extension educators and dairy consultants ABOUT Developed by Nesli Akdeniz in Biological Systems Engineering at UW-Madison as an educational and decision-support tool for dairy producers. Calculations follow established methods used in dairy ventilation design. Results are intended to give general guidance. Final decisions and outcomes remain the responsibility of the user.
Screenshots
Verdict
The clearest difference is in-app purchases: Dairy Ventilation at none against Duct Calculator's 1. Dairy Ventilation also leads on update cadence (every 2 weeks vs every 10 months) and rating (5.0 vs 4.7). On price, ratings volume, ads 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. Duct Calculator sells 1 one-off in-app purchase. Dairy Ventilation asks for nothing beyond the download.
Dairy Ventilation holds the better App Store score, 5.0 against 4.7. Both are backed by a comparable volume of ratings — 3 and 4 respectively.
Duct Calculator ships an update every 10 months, Dairy Ventilation every 2 weeks. The most recent releases landed on November 1, 2026 and October 31, 2026 respectively.
| Parameter | Duct Calculator | Dairy Ventilation |
|---|---|---|
| Price | Free | Free |
| Rating | 4.7 (3 ratings) | 5.0 (4 ratings) — better |
| Number of ratings | 3 | 4 — better |
| Update frequency | Every 10 months | Every 2 weeks — better |
| Ads | No | No |
| In-app purchases | Yes | No — better |
| Monetization | Free with in-app purchases | Free — better |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Requires iOS | 15.6 | 15.1 — better |
| Further details — not scored | ||
| Size | 44 MB | 27 MB |
| Age rating | 4+ | 4+ |
| Developer | Sachinbhai Surani | University of Wisconsin-Madison Shared Apps |
Customer experience
Duct Calculator
Dairy Ventilation
In-app purchases
Duct Calculator
- Lifetime premium$9.99
Dairy Ventilation
No in-app purchases
Questions
Is Duct Calculator free?
Is Dairy Ventilation free?
Which has better reviews, Duct Calculator or Dairy Ventilation?
Do Duct Calculator or Dairy Ventilation have ads?
Which is updated more often, Duct Calculator or Dairy Ventilation?
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