Comparison

HVAC Toolkit Ultimate vs Ductulator

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

Head to head
About

HVAC Toolkit Ultimate

This comprehensive application offers a suite of tools for HVAC professionals, including load calculations, equipment tracking, refrigerant charts, duct and pipe sizing, and psychrometric analysis. It consolidates multiple functionalities into a single, powerful utility for field and office use.

Highlights
  • Residential load calculations
  • Equipment nameplate data tracking
  • Refrigerant pressure-temperature charts
  • Superheat and subcool calculations
  • Duct and pipe sizing analysis
  • Psychrometric calculations
  • Steam table property calculations
Features
Read full description

This may just be the only HVAC app you will ever need. The HVAC Toolkit Ultimate from Carmel Software is a universal app that works on both the iPhone and iPad. It is the essential app for anyone in the HVAC industry. It is a compilation of most of the individual iPhone and iPad applications offered by Carmel Software plus bonus software. If you bought each of these apps separately, it would cost more than 2 times what the price of this app is. It includes: 1. HVAC Residential Load Calc HD (iPad version) 1. HVAC Residential Load Calcs (iPhone version) 1. HVAC Equipment Locator 2. HVAC PT Chart 3. HVAC Refrigerant Charge 4. HVAC Duct Sizer 2. HVAC Quick Load 6. ASHRAE Ventilation Calcs (iPhone version) 7. Psychrometrics 8. Steam Tables 9. HVAC Pipe Sizer - Liquid 10. HVAC Pipe Sizer - Steam 11. HVAC Pipe Sizer - Gas Low 12. HVAC Pipe Sizer - Gas High The "HVAC Residential Load Calcs" module allows you to perform comprehensive HVAC block and room-by-room load calculations for small commercial and residential buildings. You can easily use this module out in the field by taking advantage of the simplicity and power of the iPhone or iPad, and then email results back to your office. The "HVAC Equipment Locator" module allows you to track, share, and customize your equipment nameplate and maintenance data. The version here includes the ability to customize your input screens (this is usually an in-app purchase on the free stand-alone version of Locator, but it is included here). The "HVAC PT Chart" module allows you to easily view the pressure-temperature properties of 100 refrigerants. Think of this app as a digital version of the paper PT charts that you may have carried around with you in the past. The "HVAC Refrigerant Charge" module allows you to perform superheat and subcool refrigerant charge calculations on-the-fly. This app includes pressure-temperature data for over 100 common refrigerants including azeotropic (bubble/dew) versions of refrigerants. The "HVAC Duct Sizer" module allows you to perform quick and simple duct sizing analysis. You can specify the total airflow in CFM (or L/s), the aspect ratio and one of either the velocity of air or the friction loss per 100 feet (30 meters). The results include both the exact and rounded height and width (or diameter) dimensions and the calculated velocity and friction loss. In addition, you can calculate for a range of duct sizes by specifying minimum and maximum friction loss and airflow values. The "HVAC Quick Load" module allows you to quickly calculate total heating and cooling loads for a wide variety of building types. The "Psychrometrics" module allows you to easily perform single-state and mixed-air HVAC psychrometric calculations for up to 23 different combinations of input parameters. The "Steam Tables" module allows you to calculate the properties of saturated or superheated steam by specifying 2 input properties. This module is also part of the "Pipe Sizer - Steam" module discussed below. The "ASHRAE Ventilation Calcs" module allows you to perform comprehensive minimum ventilation calculations for a wide variety of commercial buildings based upon ASHRAE Standard 62.11-2007 and 2010/2013 versions. The "HVAC Pipe Sizer - Liquid" module allows you to size a pipe run for many different types of liquids (or fluids), pipe material and fitting types. The "HVAC Pipe Sizer - Steam" module allows you to size a steam pipe run, and it also includes a bonus steam table calculator. The "HVAC Pipe Sizer - Gas Low and Gas High" modules allows you to quickly size a simple low (less than or equal to 1.5 psi) and high (greater than 1.5 psi) pressure gas piping system by inputting a number of piping and gas properties. All values can be displayed in English (IP) and Metric (SI) units. We also offer all of the above modules as individual apps, too.

About

Ductulator

Instantly calculate HVAC duct sizes based on airflow, friction rate, or velocity. This tool provides accurate duct dimensions in seconds without needing charts, supporting various duct types and units.

Highlights
  • Instant duct sizing
  • Friction rate or velocity calculation
  • Multiple valid duct dimensions
  • IP and SI units support
  • Detailed sizing mode
  • Rectangular, circular, and flexible ducts
Features
Currently charting
Read full description

Size HVAC ducts instantly using airflow, friction or velocity. Get accurate duct dimensions in seconds — no charts required. • Get a range of suitable duct sizes based on friction rate or velocity. • Get multiple valid duct dimensions instantly. • Tap on Friction Rate or Velocity to toggle between calculation methods. • IP and SI units. • Detailed sizing mode to adjust the duct dimensions and air flow rates. • Supports rectangular, circular and flexible ducts. • Automatic friction and velocity updates. Calculations are based on standard air 0.075 lb/ft3 (1.2 kg/m3) in clean galvanized steel or non-metallic flexible ducts. Any feedback is welcome, and will be the basis for future updates.

Screenshots

HVAC Toolkit Ultimate4 screens
Ductulator4 screens

Verdict

The call

The clearest difference is price: Ductulator at $3.99 against HVAC Toolkit Ultimate's $59.99. Ductulator also leads on rating (4.7 vs 3.0) and ratings volume (317 vs 4). HVAC Toolkit Ultimate's advantage is iOS requirement (13.0 vs 18.6). 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

HVAC Toolkit Ultimate costs $59.99 and Ductulator $3.99 up front. Neither carries in-app purchases, so what you see is what you pay.

ReceptionRating · Positive reviews · Number of ratings

Ductulator holds the better App Store score, 4.7 against 3.0. That said, the two scores are not equally well evidenced: Ductulator has 317 ratings behind it against 4, so its average is the more settled of the two. Written reviews point the same way: 40% of HVAC Toolkit Ultimate's written reviews are positive against 50% of Ductulator's.

UpkeepUpdate frequency

HVAC Toolkit Ultimate ships an update every 6 months, Ductulator every 2 months. The most recent releases landed on October 12, 2026 and October 20, 2026 respectively.

Scorecard8 real differences · 3 level
HVAC Toolkit Ultimate versus Ductulator: the parameters behind the verdict, then further details
ParameterHVAC Toolkit UltimateDuctulator
Price$59.99$3.99 — better
Rating3.0 (4 ratings)4.7 (317 ratings) — better
Positive reviews40.0% of reviews50.0% of reviews — better
Number of ratings4317 — better
Update frequencyEvery 6 monthsEvery 2 months — better
AdsNoNo
In-app purchasesNoNo
MonetizationPaidFree — better
Best chart rank—#46 — better
DevicesiPhone, iPad, iPod — betteriPhone, iPad
Requires iOS13.0 — better18.6
Further details — not scored
Size59 MB1 MB
Age rating4+4+
DeveloperCarmel Software CorporationWassim Murr

Customer experience

HVAC Toolkit Ultimate

All ratings4 ratings
Positive50.0%
Neutral0.0%
Negative50.0%
Written reviews15 reviews
Positive40.0%
Neutral6.7%
Negative53.3%

Ductulator

All ratings317 ratings
Positive93.4%
Neutral2.2%
Negative4.4%
Written reviews22 reviews
Positive50.0%
Neutral13.6%
Negative36.4%

Bugs and requests

HVAC Toolkit Ultimate

Not enough reviews yet to summarise bugs or requests.

Ductulator

Reported bugs

4 issues
  • Decimal point doesn't work on calculator
  • New flex option isn't working properly
  • Friction rate can't be changed in the latest version
  • Skips duct sizes (e.g., 24-26)

Requested features

5 requests
  • Ability to pick duct size and see CFM
  • Include flat oval ducts
  • Option to select round or square duct
  • Ability to enter duct size and get CFM
  • Option for flex duct

In-app purchases

None

HVAC Toolkit Ultimate

No in-app purchases

None

Ductulator

No in-app purchases

Questions

Is HVAC Toolkit Ultimate free?
HVAC Toolkit Ultimate costs $59.99, with no in-app purchases.
Is Ductulator free?
Ductulator costs $3.99, with no in-app purchases.
Which has better reviews, HVAC Toolkit Ultimate or Ductulator?
Ductulator is rated higher. HVAC Toolkit Ultimate averages 3.0 out of 5 from 4 ratings, while Ductulator averages 4.7 from 317 ratings.
Do HVAC Toolkit Ultimate or Ductulator have ads?
Neither HVAC Toolkit Ultimate nor Ductulator shows ads.
Which is updated more often, HVAC Toolkit Ultimate or Ductulator?
HVAC Toolkit Ultimate ships an update every 6 months, and Ductulator every 2 months. Most recently, HVAC Toolkit Ultimate was updated on October 12, 2026 and Ductulator on October 20, 2026.

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