# HVAC Pipe Sizer vs Ductulator

The clearest difference is in-app purchases: Ductulator at none against HVAC Pipe Sizer's 1. Ductulator also leads on ratings volume (353 vs 1) and update cadence (every 2 months vs every 10 months). HVAC Pipe Sizer's advantage is review sentiment (80% vs 50%) and rating (5.0 vs 4.7). On ads, device support and iOS requirement there is nothing between them.

HVAC Pipe Sizer costs $7.99 and Ductulator $3.99 up front. HVAC Pipe Sizer sells 1 one-off in-app purchase. Ductulator asks for nothing beyond the download.

HVAC Pipe Sizer holds the better App Store score, 5.0 against 4.7. That said, the two scores are not equally well evidenced: Ductulator has 353 ratings behind it against 1, so its average is the more settled of the two. Written reviews point the same way: 80% of HVAC Pipe Sizer's written reviews are positive against 50% of Ductulator's.

HVAC Pipe Sizer ships an update every 10 months, Ductulator every 2 months. The most recent releases landed on October 24, 2026 and October 25, 2026 respectively.

## The numbers

| Metric | HVAC Pipe Sizer | Ductulator |
| --- | --- | --- |
| Price | $7.99 | **$3.99** |
| Rating | **[5.0 (1 ratings)](https://appshunter.io/ios/app/hvac-pipe-sizer-gas-plus/id342239204/reviews)** | [4.7 (353 ratings)](https://appshunter.io/ios/app/ductulator-duct-sizing/id1474939475/reviews) |
| Number of ratings | 1 | **353** |
| Positive reviews | **80.0% of reviews** | 50.0% of reviews |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | Every 10 months | **Every 2 months** |
| Monetization | Paid | **Free** |
| Best chart rank | — | **#121** |
| Size | 1 MB | 1 MB |
| Requires iOS | **17.0** | 18.6 |
| Devices | iPhone, iPad | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Carmel Software Corporation](https://appshunter.io/developer/317970398) | [Wassim Murr](https://appshunter.io/developer/1474939474) |

## What reviewers say

### HVAC Pipe Sizer

[App page](https://appshunter.io/ios/app/hvac-pipe-sizer-gas-plus/id342239204)

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:** macOS Compatibility, Vision Pro support

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| HVAC Equipment Locator | $9.99 | one-time |


### Ductulator

[App page](https://appshunter.io/ios/app/ductulator-duct-sizing/id1474939475)

**Currently charting:** #121 Top Paid · Productivity (US App Store)

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:** macOS Compatibility, Vision Pro support

**In-app purchases:** none

**What reviewers like**

- 👍 Very helpful for duct sizing
- 👍 Easy to use in the field
- 👍 Saves time
- 👍 Seamless imperial/metric transitions
- 👍 Excellent tool for duct design

**What reviewers complain about**

- 👎 App should be free
- 👎 Functionality is pointless for some needs
- 👎 Doesn't help with traditional residential HVAC duct sizing
- 👎 App is a scam
- 👎 Decimal point doesn't work

**Reported bugs**

- 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**

- 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


## Frequently asked questions

### Is HVAC Pipe Sizer free?

HVAC Pipe Sizer costs $7.99, and also offers in-app purchases.

### Is Ductulator free?

Ductulator costs $3.99, with no in-app purchases.

### Which has better reviews, HVAC Pipe Sizer or Ductulator?

HVAC Pipe Sizer is rated higher. HVAC Pipe Sizer averages 5.0 out of 5 from 1 ratings, while Ductulator averages 4.7 from 353 ratings.

### Do HVAC Pipe Sizer or Ductulator have ads?

Neither HVAC Pipe Sizer nor Ductulator shows ads.

### Which is updated more often, HVAC Pipe Sizer or Ductulator?

HVAC Pipe Sizer ships an update every 10 months, and Ductulator every 2 months. Most recently, HVAC Pipe Sizer was updated on October 24, 2026 and Ductulator on October 25, 2026.

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*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*