Duct Calculator vs RiDATA
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
Duct Calculator
This app allows HVAC professionals to quickly and accurately size new ducts or calculate the performance of existing ones. It supports both round and rectangular ductwork, offering precise calculations through direct entry or intuitive sliders. The tool provides live updates and outputs key performance metrics.
- Size round and rectangular ductwork
- Adjust airflow, diameter, width, and height
- Direct number entry for precision
- Lockable dimensions for 'what-if' scenarios
- Live update of calculated values
- Outputs velocity and pressure drop
- Supports IP and SI units
Read full descriptionHide full description
The Duct Calculator App for iPhone/iPad is a modern take on a the classic duct sizing wheel, allowing HVAC engineers, designers and contractors quickly and accurately size a new duct or calculate the performance of an existing duct on your iOS devices. Size both round and rectangular ductwork with the ease of a traditional Ductulator. Adjust the airflow, diameter, width or height sliders with your thumbs. Get maximum precision by entering numbers directly into the the calculator. Lock friction rate, diameter or width or height to make the calculations you need for your design. Live update of the calculated values allows you to see the impact of the changes immediately. Outputs velocity for both round and rectangular ducts. PERFORM QUICK AND ACCURATE CALCULATIONS: Enter the airflow and sizes in directly as numbers for maximum precision. - or - Use the airflow and size sliders for quick calculations. Shows live equivalent round/rectangular duct sizes. Specific dimensions can be locked to allow specific what-ifs to be quickly calculated. Works for both IP and SI units. You can select from a range of duct roughness categories. Designed to allow quick calculations anywhere, anytime, it is ideal for the HVAC designer or contractor. HOW TO USE: Locking Dimensions: The lock symbols to the right of the duct dimensions indicate if that particular dimension is locked when calculating new equivalent values when a dimension is updated. The Diameter can be locked or unlocked. The Width or Height can be locked, but not both. Using the Sliders: Move the sliders for Airflow, Duct Diameter, Width and Height up and down to match the desired duct size to calculate velocity and pressure drop for. The Diameter, Width and Height will change such that the equivalent size is shown: Changing the diameter will updated either the equivalent Width or the Height, depending on which dimension is unlocked. Changing the Width or Height will update the equivalent Diameter if it is unlocked, or the other rectangular duct dimension of the Diameter size is locked. Direct Entry: The values for Airflow, Diameter, Width and Height can be directly edited in the text boxes to allow quick entry of exact numbers. Invalid entries will generate an error message, and must be corrected prior to the calculations updating. Output: The values for the calculated Velocity for Round Duct and Rectangular Duct are shown, as is the Pressure Drop per Length value. NOTES: This application (App) is provided for use by qualified HVAC engineers and designers in the design of air handling systems and is not a substitute for appropriate design services. When in doubt, contact a design professional.
RiDATA
Expand your iOS device's storage with an external RiDATA device. Easily transfer and manage photos, videos, audio, and documents across different platforms and devices.
- External storage device compatibility
- File exchange across devices/platforms
- Picture browser
- Video player
- Audio player
- Document browser
- Camera function
Read full descriptionHide full description
The Application requires using with RiDATA external storage device, and provides iOS device for capacity expansion. Exchange files with different devices and platforms with ease. Features: - Provide picture browser, including iOS photos. - Provide video player, including iOS photos. - Provide audio player, including iTune music. (Doesn't support music downloaded from iTune) - Provide document browser. - Provide camera function. Support File Format: - Picture: BMP, GIF, JPG, PNG, TIF - Video: M4V, MOV, MP4 - Audio: M4A, MP3, WAV - Document: DOC, DOCX, PPT, PPTX, XLS, XLSX, KEYNOTES, NUMBERS, PAGES, HTML, PDF, RTF, RTFD, TXT
Screenshots
Verdict
The clearest difference is price: RiDATA at Free against Duct Calculator's $19.99. RiDATA also leads on iOS requirement (8.0 vs 15.0). Duct Calculator's advantage is rating (4.5 vs 3.3) and review sentiment (57% vs 17%). On update cadence, ads, in-app purchases and monetization model 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
RiDATA is free to download; Duct Calculator costs $19.99 up front. Neither carries in-app purchases, so what you see is what you pay.
Duct Calculator holds the better App Store score, 4.5 against 3.3. That said, the two scores are not equally well evidenced: Duct Calculator has 189 ratings behind it against 3, so its average is the more settled of the two. Written reviews point the same way: 57% of Duct Calculator's written reviews are positive against 17% of RiDATA's.
Both ship on a similar rhythm, roughly every 2 months. Both last shipped on November 2, 2026.
| Parameter | Duct Calculator | RiDATA |
|---|---|---|
| Price | $19.99 | Free — better |
| Rating | 4.5 (189 ratings) — better | 3.3 (3 ratings) |
| Positive reviews | 57.1% of reviews — better | 16.7% of reviews |
| Number of ratings | 189 — better | 3 |
| Update frequency | Every 2 months | Every 2 months |
| Ads | No | No |
| In-app purchases | No | No |
| Monetization | Free | Free |
| Devices | iPhone, iPad, iPod, Mac — better | iPhone, iPad, iPod |
| Requires iOS | 15.0 | 8.0 — better |
| Further details — not scored | ||
| Size | 2 MB | 45 MB |
| Age rating | 4+ | 4+ |
| Developer | Pheinex, LLC | Siliconmotion |
Customer experience
Duct Calculator
RiDATA
In-app purchases
Duct Calculator
No in-app purchases
RiDATA
No in-app purchases
Questions
Is Duct Calculator free?
Is RiDATA free?
Which has better reviews, Duct Calculator or RiDATA?
Do Duct Calculator or RiDATA have ads?
Which is updated more often, Duct Calculator or RiDATA?
Other comparisons















