Comparison

HVAC Pipe Sizer vs HydroCalc Plus

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

Head to head
About

HVAC Pipe Sizer

Calculate gas piping systems for low and high pressure. Input flow, pressure, or diameter to find pipe sizes, velocity, and equivalent lengths. Supports English and metric units, with extensive pipe fitting data.

Highlights
  • Low and high pressure gas pipe sizing
  • Calculate flow, pressure drop, diameter, and velocity
  • Universal app for iPhone and iPad
  • English and metric unit support
  • Built-in pipe fitting equivalent length tables
  • Slider controls for quick adjustments
Features
Read full description

The "HVAC Pipe Sizer - Gas Plus" application allows you to quickly size a simple low (less than or equal to 1.5 psi) and/or high (greater than 1.5 psi) pressure gas piping system by inputting a number of piping and gas properties. This application combines the functionality of our popular "HVAC Pipe Sizer - Gas Low" and "HVAC Pipe Sizer - Gas High" applications. This app is now a universal app meaning that it works on both the iPhone and iPad and adjusts its screen size accordingly. For low pressure gas piping, you can specify the total gas flow in ft3/hr (m3/hr) and one of either pressure drop (in. wg or Pa), pipe internal diameter (inches) or gas velocity (ft/s) parameters. The results include both the exact and nominal pipe diameters and the calculated velocity and total pipe equivalent length. If you are analyzing an existing pipe system, there is an option to input the existing pipe internal diameter and one of either pressure drop or gas velocity parameters to derive the calculated gas flow and other remaining properties. For high pressure gas piping, you can specify the total gas flow in ft3/hr (m3/hr), the upstream pressure (psig or kPa), and one of either downstream pressure (psig or kPa), pipe internal diameter (inches) or gas velocity (ft/s) parameters. The results include both the exact and nominal pipe diameters and the calculated velocity and total pipe equivalent length. If you are analyzing an existing pipe system, there is an option to input the existing pipe internal diameter, the upstream pressure, and one of either downstream pressure or gas velocity parameters to derive the calculated gas flow and other remaining properties. You can specify additional parameters such as the type of gas, various properties of the gas, the pipe material type, the total length of pipe, quantities for up to 11 different types of pipe fittings, and much more. You can also choose to display values in either english or metric units. This application includes built-in pipe fitting equivalent length and nominal pipe sizing tables for a wide variety of pipe material types and diameters. This application uses slider controls that allow you to quickly increment or decrement the input values and immediately observe the calculated results. You can also manually input exact values. This app now includes the HVAC Equipment Locator. Click here for details: http://bit.ly/1yTq539 The "HVAC Pipe Sizer - Gas Plus" application was designed by Carmel Software Corporation, a leader in HVAC design software since 1995. In fact, Autodesk (the makers of AutoCAD) acquired our load calculation software and incorporated it into their leading 3D modeling software called Revit. In addition, we developed a number of customized apps for ASHRAE, DNV GL, and other organizations. We also offer the following additional apps for the iPhone and iPad: 1. HVAC Residential Load Calcs for iPhone and iPad 2. HVAC Quick Load Plus 3. HVAC Quick Load 4. HVAC Toolkit 5. HVAC Pipe Sizer – Gas Low Pressure 6. HVAC Pipe Sizer - Gas High Pressure 7. HVAC Pipe Sizer – Liquid 8. HVAC Pipe Sizer – Steam 9. Steam Tables 10. Psychrometric Plus 11. Psychrometric LT 12. HVAC Pipe Sizer Plus 13. HVAC Pipe Sizer Gas Plus 14. HVAC Toolkit Ultimate 15. HVAC Equipment Locator 16. HVAC ResLoad-J 17. HVAC Psych HD

About

HydroCalc Plus

A professional tool for hydraulic engineers to calculate pressure losses in piping systems. It supports US and SI units, offers an extensive pipe material and fittings database, and includes inverse calculations for design optimization.

Highlights
  • Friction head loss calculation (Hazen-Williams)
  • US and SI unit support
  • Extensive pipe material library
  • Fittings and valves database
  • Inverse calculation mode
  • Real-time results (velocity, losses)
Features
Read full description

Professional hydraulic engineering tool for calculating pressure losses in piping systems. Essential for engineers, plumbers, and contractors designing water distribution networks. Key Features: Calculate friction head losses using industry-standard Hazen-Williams equation Support for both US (ft, gpm, psi) and SI (m, lps, bar) units Extensive pipe material library with pre-defined roughness coefficients (C-factors) Complete fittings and valves database including elbows, tees, valves, contractions, and expansions Inverse calculations to determine optimal pipe diameter, flow rate, or length for target head loss Real-time results showing velocity, friction loss, minor losses, and total system head loss What Sets Pro Apart: Unlike basic calculators, HydroCalc Pro accounts for both major losses (pipe friction) and minor losses (fittings and valves). The app includes a comprehensive database of K-factors for various components, allowing accurate total system pressure loss calculations. Perfect For: Water supply system design Irrigation network planning HVAC piping calculations Fire protection systems Industrial fluid transport Educational purposes in hydraulic engineering Technical Capabilities: The app considers all critical factors affecting pressure loss: flow velocity, pipe diameter, internal roughness, pipe length, and fitting configurations. Materials include PVC, polyethylene, steel, cast iron, concrete, and more with accurate C-factors ranging from 120-150. Inverse Calculation Mode: Unique feature allowing backward calculations - determine required pipe size for allowable head loss, maximum flow capacity, or optimal pipe length for your system constraints. Simple, intuitive interface with instant results. No internet connection required. Professional-grade calculations in your pocket. Note: Premium modules are available in English and Spanish.

Screenshots

HVAC Pipe Sizer4 screens
HydroCalc Plus4 screens

Verdict

The call

The clearest difference is update cadence: HydroCalc Plus at every 3 weeks against HVAC Pipe Sizer's every 12 months. HydroCalc Plus also leads on review sentiment (100% vs 80%) and price ($3.99 vs $7.99). On rating, ratings volume, ads and in-app purchases 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 Pipe Sizer costs $7.99 and HydroCalc Plus $3.99 up front. HVAC Pipe Sizer sells 1 one-off in-app purchase and HydroCalc Plus sells 4 one-off in-app purchases. Whichever you choose, the download price is not the number that matters.

ReceptionRating · Positive reviews · Number of ratings

On the App Store both sit at effectively the same score — 5.0 for HVAC Pipe Sizer against 5.0 for HydroCalc Plus. Both are backed by a comparable volume of ratings — 1 and 1 respectively. Written reviews are what separate them: 80% of HVAC Pipe Sizer's written reviews are positive against 100% of HydroCalc Plus's.

UpkeepUpdate frequency

HVAC Pipe Sizer ships an update every 12 months, HydroCalc Plus every 3 weeks. The most recent releases landed on September 9, 2026 and August 31, 2026 respectively.

Scorecard3 real differences · 7 level
HVAC Pipe Sizer versus HydroCalc Plus: the parameters behind the verdict, then further details
ParameterHVAC Pipe SizerHydroCalc Plus
Price$7.99$3.99 — better
Rating5.0 (1 ratings)5.0 (1 ratings)
Positive reviews80.0% of reviews100.0% of reviews — better
Number of ratings11
Update frequencyEvery 12 monthsEvery 3 weeks — better
AdsNoNo
In-app purchasesYesYes
MonetizationPaidPaid
DevicesiPhone, iPad, iPodiPhone, iPad, iPod
Requires iOS15.615.1 — better
Further details — not scored
Size18 MB34 MB
Age rating4+4+
DeveloperCarmel Software CorporationTransparent Blue Water LLC

Customer experience

HVAC Pipe Sizer

All ratings1 ratings
Positive100.0%
Neutral0.0%
Negative0.0%
Written reviews5 reviews
Positive80.0%
Neutral0.0%
Negative20.0%

HydroCalc Plus

All ratings1 ratings
Positive100.0%
Neutral0.0%
Negative0.0%
Written reviews1 reviews
Positive100.0%
Neutral0.0%
Negative0.0%

In-app purchases

1 purchases

HVAC Pipe Sizer

One-time1
  • HVAC Equipment Locator$9.99
4 purchases

HydroCalc Plus

One-time4
  • Pump Power Calculator$1.99
  • System Curve Generator$1.99
  • Pipe Database$1.99
Show 1 more
  • Industrial Fluids Pack$2.99

Questions

Is HVAC Pipe Sizer free?
HVAC Pipe Sizer costs $7.99, and also offers in-app purchases.
Is HydroCalc Plus free?
HydroCalc Plus costs $3.99, and also offers in-app purchases.
Which has better reviews, HVAC Pipe Sizer or HydroCalc Plus?
HVAC Pipe Sizer and HydroCalc Plus are both rated 5.0 out of 5 on the App Store, from 1 and 1 ratings respectively.
Do HVAC Pipe Sizer or HydroCalc Plus have ads?
Neither HVAC Pipe Sizer nor HydroCalc Plus shows ads.
Which is updated more often, HVAC Pipe Sizer or HydroCalc Plus?
HVAC Pipe Sizer ships an update every 12 months, and HydroCalc Plus every 3 weeks. Most recently, HVAC Pipe Sizer was updated on September 9, 2026 and HydroCalc Plus on August 31, 2026.

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