Comparison

Duct Calculator vs TagGuard

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

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.

Highlights
  • 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
Features
Read 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.

About

TagGuard

Features
Read full description

n your bag, under your car — what if there's a tracker that isn't yours? TagGuard finds hidden Bluetooth trackers (AirTag, Galaxy SmartTag, Tile, Chipolo, Google Find My) and makes sure your family knows the moment something is wrong. ■ Hidden tracker detection • One-tap scan — results in seconds • Risk score — sightings, time together, distance traveled and distinct places are computed so you're only warned about real threats • Radar finder — the gauge climbs and vibration speeds up as you get closer; find it under the couch or inside the car • Route evidence — every shared movement is mapped, ready to reference in a police report ■ Family safety net (optional) • When tracking risk is detected, connected family members are alerted automatically — even before you notice • SOS — hold for 2 seconds to share your live location with family • SOS location texts reach family even without the app • Everything is end-to-end encrypted — even our server can't read it ■ Caring for parents • Connect with a single 6-digit code (no sign-up) • Once a parent turns on consent, you can request their location whenever you're worried • Every share posts a notification on the parent's phone — this is not covert monitoring ■ Privacy principles • Tracker detection runs 100% on your phone • Location leaves your phone only for family sharing you start yourself (end-to-end encrypted) • No ads. No account. Free to start.

Screenshots

Duct Calculator4 screens
TagGuard4 screens

Verdict

The call

The clearest difference is price: TagGuard at Free against Duct Calculator's $19.99. TagGuard also leads on iOS requirement (13.0 vs 15.0). On 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

CostPrice · In-app purchases · Ads · Monetization

TagGuard is free to download; Duct Calculator costs $19.99 up front. Neither carries in-app purchases, so what you see is what you pay.

Scorecard2 real differences · 8 level
Duct Calculator versus TagGuard: the parameters behind the verdict, then further details
ParameterDuct CalculatorTagGuard
Price$19.99Free — better
Rating4.5 (189 ratings) — better—
Positive reviews57.1% of reviews—
Number of ratings189 — better—
Update frequencyEvery 2 months—
AdsNoNo
In-app purchasesNoNo
MonetizationFree—
DevicesiPhone, iPad, iPod, Mac — betteriPhone, iPad, iPod
Requires iOS15.013.0 — better
Further details — not scored
Size2 MB50 MB
Age rating4+4+
DeveloperPheinex, LLCHeung Gi Kim

In-app purchases

None

Duct Calculator

No in-app purchases

None

TagGuard

No in-app purchases

Questions

Is Duct Calculator free?
Duct Calculator costs $19.99, with no in-app purchases.
Is TagGuard free?
TagGuard is free to download, with no in-app purchases.
Do Duct Calculator or TagGuard have ads?
Neither Duct Calculator nor TagGuard shows ads.

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