Comparison

Digiduct vs Unit Converter HVAC

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

Head to head
About

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.

Highlights
  • 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
Features
Read full description

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.

About

Unit Converter HVAC

Features
Read full description

HVAC Unit Converter Pro helps HVAC technicians, engineers, refrigeration mechanics, and contractors convert between units instantly. Convert between all common air conditioning and refrigeration units instantly across 8 categories and 40+ unit types - eliminating calculation errors on job sites. 8 CONVERSION CATEGORIES: Temperature - °F, °C, K, °R (Rankine) for climate zones and equipment specs Pressure - PSI, kPa, bar, in. Hg, mm Hg, atm, Pa, in. w.c. (static pressure), microns (vacuum) for gauges and evacuation Energy & Heat - BTU, kJ, kcal, Wh, therm for load calculations Airflow (CFM) - CFM, L/s, m³/h, m³/s, m³/min for ductwork and ventilation Length & Duct - in, ft, mm, cm, m for duct sizing and pipe runs Area Calculations - ft², m², in² for room dimensions and surface area Volume & Capacity - gal, L, ft³, m³ for tank and system volumes Power & Output - BTU/h, W, kW, ton (refrigeration), hp, kcal/h for equipment ratings SMART FEATURES: Instant Conversion - Results update as you type, no button press needed Bidirectional Conversion - One tap to reverse conversion direction instantly Swap Units - Toggle between any unit pair in the same category Works 100% Offline - Field calculations without internet connection Accuracy Verified - Professional-grade precision for system design English & Spanish Support - Bilingual interface for diverse teams WHY HVAC PROFESSIONALS USE THIS APP: Eliminates manual conversion errors that cause mistakes Faster unit calculations than reference tables and charts Cross-checks between imperial and metric systems instantly Prevents equipment sizing errors from unit mistakes Works on every job site without cellular connection Dark theme prevents eye strain during outdoor work CONVERSION EXAMPLES HVAC TECHS USE DAILY: PSI to kPa for pressure readings on gauge conversions BTU to kW for international equipment specifications CFM to m³/s for ductwork design in metric regions °F to °C for climate zone design temperature conversions Tons to kW for heat pump capacity documentation BTU/h to watts for electrical load calculations PERFECT FOR: HVAC technicians on air conditioning service calls HVAC field technicians calculating refrigeration requirements Refrigeration mechanics sizing refrigerant lines AC contractors preparing equipment specifications HVAC design engineers in international projects HVAC apprentices learning unit conversions Building maintenance engineers managing equipment Commercial HVAC system commissioning work A tool trusted by HVAC technician teams nationwide. Part of HVACTools Suite - the complete HVAC technician and refrigeration calculator app collection for field diagnostics and system design. OPTIONAL PRO UPGRADE — $2.99 ONE-TIME IN-APP PURCHASE The following features require a separate one-time in-app purchase. They are not required to use the calculator: • Unlimited saved calculation history • PDF export of results • Dark theme • Ad-free experience

Screenshots

Digiduct4 screens
Unit Converter HVAC4 screens

Verdict

The call

The clearest difference is price: Digiduct at Free against Unit Converter HVAC's $0.99. Digiduct also leads on in-app purchases (none vs 1). Unit Converter HVAC's advantage is update cadence (every 3 weeks vs every 2 months) and iOS requirement (13.0 vs 26.2). On 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

CostPrice · In-app purchases · Ads · Monetization

Digiduct is free to download; Unit Converter HVAC costs $0.99 up front. Unit Converter HVAC sells 1 one-off in-app purchase. Digiduct asks for nothing beyond the download.

UpkeepUpdate frequency

Digiduct ships an update every 2 months, Unit Converter HVAC every 3 weeks. Both last shipped on October 24, 2026.

Scorecard4 real differences · 5 level
Digiduct versus Unit Converter HVAC: the parameters behind the verdict, then further details
ParameterDigiductUnit Converter HVAC
PriceFree — better$0.99
Rating4.6 (11 ratings) — better—
Number of ratings11 — better—
Update frequencyEvery 2 monthsEvery 3 weeks — better
AdsNoNo
In-app purchasesNo — betterYes
MonetizationAd-supported—
DevicesiPhone, iPadiPhone, iPad, iPod — better
Requires iOS26.213.0 — better
Further details — not scored
Size4 MB34 MB
Age rating4+17+
DeveloperSyska Hennessy GroupRizvan Adzhoian

In-app purchases

None

Digiduct

No in-app purchases

1 purchases

Unit Converter HVAC

One-time1
  • Pro Unlock$2.99

Questions

Is Digiduct free?
Digiduct is free to download, with no in-app purchases.
Is Unit Converter HVAC free?
Unit Converter HVAC costs $0.99, and also offers in-app purchases.
Do Digiduct or Unit Converter HVAC have ads?
Neither Digiduct nor Unit Converter HVAC shows ads.
Which is updated more often, Digiduct or Unit Converter HVAC?
Digiduct ships an update every 2 months, and Unit Converter HVAC every 3 weeks. Most recently, Digiduct was updated on October 24, 2026 and Unit Converter HVAC on October 24, 2026.

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