Comparison

Duct Calculator Elite vs HVAC Decoder

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

Head to head
About

Duct Calculator Elite

This app simplifies HVAC duct sizing calculations. It computes duct size, velocity, pressure drop, and flow rate with an intuitive interface. Supports various units and duct materials for precise HVAC design.

Highlights
  • Calculate duct size, velocity, pressure drop, flow rate
  • Duct Size by Airflow mode
  • Duct Size by Dimension mode
  • Pressure Drop calculations
  • Customizable units and duct materials
  • Uses ASHRAE Handbook friction loss equations
Features
Read full description

Duct Calculator Elite™ replaces your ductulator wheel with fast, precise duct sizing built on the friction-loss equations of the ASHRAE Handbook — Fundamentals. Trusted by HVAC professionals, mechanical engineers, and contractors since 2013. One price — no subscriptions, no ads, no accounts. THREE CALCULATORS, ONE TAP APART • DUCT SIZE BY AIRFLOW — Set airflow and either velocity or friction, and solve for round and rectangular duct dimensions. Specify the rectangular aspect ratio to match your available space. The nearest standard round and rectangular sizes are shown with the friction they actually run at. • DUCT SIZE BY DIMENSION — Enter a round diameter or rectangular height and width, then lock airflow, velocity, or friction and solve for the remaining variables. • PRESSURE DROP — Convert between duct length, pressure drop, and friction. Find the exact pressure drop of a given installation, or the maximum duct length that maintains your design pressure drop. DESIGN TOOLS • FRICTION RATE — Enter your available static pressure and duct run, add fittings from a built-in list of typical equivalent lengths (elbows, tees, wyes, supply boots), and get your total effective length and target friction rate — the Manual D style residential design workflow. Then send the result straight into Duct Size by Airflow with one tap. • AIRFLOW FROM HEAT LOAD — Enter a sensible heat load and temperature difference to get the required airflow, corrected for air density. ENGINEERING-GRADE MATH Solves the Colebrook friction-factor equation directly for each duct material's surface roughness — the same method behind the ASHRAE friction chart — rather than interpolating from lookup tables. Roughness values come from Table 1 of the 2025 ASHRAE Handbook — Fundamentals, and the app shows you the one it used. Rectangular results use the Huebscher equivalent-diameter equation; air density is corrected for your temperature and elevation, and air viscosity for your temperature, so results hold up at altitude and outside room temperature. Below the turbulent range where the published methods agree, results are flagged as approximate. PRECISE ENTRY, BUILT FOR THE FIELD Type exact values directly in place — no cumbersome sliders, no pop-up entry screens. Confirm with a tap and every dependent value recalculates instantly. A clean layout keeps every result in view as you work, and everything runs fully offline. CONFIGURED FOR REAL JOB CONDITIONS • Duct dimensions: inches, centimeters, or millimeters • Airflow: CFM, cubic feet per second, cubic meters per second, cubic meters per hour, or liters per second • Velocity: feet per second, feet per minute, or meters per second • Pressure loss: inches of water per 100 ft or pascals per meter • Duct materials: galvanized steel, spiral steel, galvanized spiral (corrugated), aluminum, uncoated carbon steel, PVC plastic pipe, concrete, phenolic duct (pre-insulated), flexible duct (metallic), flexible duct (helix core, insulated), fibrous glass liner (spray coated), and fibrous glass liner (faced, smooth) • Air temperature (°F, °C, K) and elevation (feet or meters) corrections The next time you head to a meeting or out to the job site, leave the ductulator at home — everything you need is on your iPhone or iPad. Questions or ideas for the next version? Email techsupport@cyberprodigy.com — we read every message.

About

HVAC Decoder

Decode HVAC model and serial numbers from major brands. This utility app provides thousands of model numbers and can email search results. It supports a wide range of HVAC equipment and offers close matches for unknown numbers.

Highlights
  • Decode HVAC model numbers
  • Decode HVAC serial numbers
  • Supports major HVAC brands
  • Thousands of model numbers
  • Email search results
  • Close match functionality
  • Report missing data
Features
Currently charting
Read full description

This app will decode the model number nomenclature of most HVAC companies. It has all the major brand names with many thousands of model numbers. It will also decode the serial number for many HVAC companies. It has the ability to email the search results in HTML format via an installed mail client. App is effective at decoding model and serial numbers for packaged units, air conditioners / condensing units, air handlers, evaporator coils, furnaces, heat pumps, boilers, chillers, split systems / mini splits, geothermal systems, and more.  If the model number is not found exactly it will try a close match. If there is no close match it will give you the option to report missing data. The data is constantly updated and purchase of the app gets you free updates forever.

Screenshots

Duct Calculator Elite4 screens
HVAC Decoder4 screens

Verdict

The call

The clearest difference is rating: Duct Calculator Elite at 4.8 against HVAC Decoder's 4.0. Duct Calculator Elite also leads on ratings volume (232 vs 28). HVAC Decoder's advantage is update cadence (every 3 months vs every 15 months) and review sentiment (69% vs 50%). On price, 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

CostPrice · In-app purchases · Ads · Monetization

Duct Calculator Elite costs $9.99 and HVAC Decoder $9.99 up front. Neither carries in-app purchases, so what you see is what you pay.

ReceptionRating · Positive reviews · Number of ratings

Duct Calculator Elite holds the better App Store score, 4.8 against 4.0. That said, the two scores are not equally well evidenced: Duct Calculator Elite has 232 ratings behind it against 28, so its average is the more settled of the two. Written reviews complicate that: 50% of Duct Calculator Elite's written reviews are positive against 69% of HVAC Decoder's, so the app with the better star average is not the one people write more warmly about.

UpkeepUpdate frequency

Duct Calculator Elite ships an update every 15 months, HVAC Decoder every 3 months. The most recent releases landed on September 28, 2026 and September 21, 2026 respectively.

Scorecard5 real differences · 6 level
Duct Calculator Elite versus HVAC Decoder: the parameters behind the verdict, then further details
ParameterDuct Calculator EliteHVAC Decoder
Price$9.99$9.99
Rating4.8 (232 ratings) — better4.0 (28 ratings)
Positive reviews50.0% of reviews68.8% of reviews — better
Number of ratings232 — better28
Update frequencyEvery 15 monthsEvery 3 months — better
AdsNoNo
In-app purchasesNoNo
MonetizationPaidPaid
Best chart rank—#200 — better
DevicesiPhone, iPad, iPodiPhone, iPad, iPod
Requires iOS15.614.0 — better
Further details — not scored
Size13 MB6 MB
Age rating4+4+
DeveloperCyberprodigy LLCCharles Cope

Customer experience

Duct Calculator Elite

All ratings232 ratings
Positive95.3%
Neutral2.2%
Negative2.6%
Written reviews18 reviews
Positive50.0%
Neutral11.1%
Negative38.9%

HVAC Decoder

All ratings28 ratings
Positive71.4%
Neutral10.7%
Negative17.9%
Written reviews16 reviews
Positive68.8%
Neutral18.8%
Negative12.5%

In-app purchases

None

Duct Calculator Elite

No in-app purchases

None

HVAC Decoder

No in-app purchases

Questions

Is Duct Calculator Elite free?
Duct Calculator Elite costs $9.99, with no in-app purchases.
Is HVAC Decoder free?
HVAC Decoder costs $9.99, with no in-app purchases.
Which has better reviews, Duct Calculator Elite or HVAC Decoder?
Duct Calculator Elite is rated higher. Duct Calculator Elite averages 4.8 out of 5 from 232 ratings, while HVAC Decoder averages 4.0 from 28 ratings.
Do Duct Calculator Elite or HVAC Decoder have ads?
Neither Duct Calculator Elite nor HVAC Decoder shows ads.
Which is updated more often, Duct Calculator Elite or HVAC Decoder?
Duct Calculator Elite ships an update every 15 months, and HVAC Decoder every 3 months. Most recently, Duct Calculator Elite was updated on September 28, 2026 and HVAC Decoder on September 21, 2026.

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