# HVAC Pipe Sizer vs Piping Engineer's Toolbox

The clearest difference is in-app purchases: HVAC Pipe Sizer at none against Piping Engineer's Toolbox's 3. HVAC Pipe Sizer also leads on update cadence (every 9 months vs every 21 months). Piping Engineer's Toolbox's advantage is iOS requirement (15.6 vs 17.0). On price, ads and device support there is nothing between them.

HVAC Pipe Sizer costs $4.99 and Piping Engineer's Toolbox $4.99 up front. Piping Engineer's Toolbox sells 3 in-app purchases, starting at $2.99 per 7 days. HVAC Pipe Sizer asks for nothing beyond the download.

HVAC Pipe Sizer ships an update every 9 months, Piping Engineer's Toolbox every 21 months. The most recent releases landed on November 6, 2026 and November 8, 2026 respectively.

## The numbers

| Metric | HVAC Pipe Sizer | Piping Engineer's Toolbox |
| --- | --- | --- |
| Price | $4.99 | $4.99 |
| Rating | **[5.0 (2 ratings)](https://appshunter.io/ios/app/hvac-pipe-sizer-gas-low/id341688321/reviews)** | — |
| Number of ratings | **2** | — |
| Positive reviews | 100.0% of reviews | — |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | **Every 9 months** | Every 21 months |
| Monetization | Paid | — |
| Size | 1 MB | 57 MB |
| Requires iOS | 17.0 | **15.6** |
| Devices | iPhone, iPad | **iPhone, iPad, iPod** |
| Age rating | +4 | +4 |
| Developer | [Carmel Software Corporation](https://appshunter.io/developer/317970398) | [Ashvin Kevadiya](https://appshunter.io/developer/1756324971) |

## What reviewers say

### HVAC Pipe Sizer

[App page](https://appshunter.io/ios/app/hvac-pipe-sizer-gas-low/id341688321)

Quickly size low-pressure gas piping systems by inputting flow, pressure drop, diameter, or velocity. Includes detailed gas and pipe properties, fitting data, and unit conversion.

**Highlights:** Low pressure gas pipe sizing, Input flow, pressure drop, diameter, or velocity, Calculate exact and nominal pipe diameters, Specify gas and pipe properties, Includes pipe fitting equivalent lengths, English and metric unit display

**Features:** macOS Compatibility, Vision Pro support

**In-app purchases:** none


### Piping Engineer's Toolbox

[App page](https://appshunter.io/ios/app/piping-engineers-toolbox/id6738736451)

**Features:** macOS Compatibility, Vision Pro support

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Weekly Subscription | $2.99 | per 7 days |
| Monthly Subscription | $5.99 | per month |
| Yearly Subscription | $14.99 | per year |


## Frequently asked questions

### Is HVAC Pipe Sizer free?

HVAC Pipe Sizer costs $4.99, with no in-app purchases.

### Is Piping Engineer's Toolbox free?

Piping Engineer's Toolbox costs $4.99, and also offers in-app purchases.

### Do HVAC Pipe Sizer or Piping Engineer's Toolbox have ads?

Neither HVAC Pipe Sizer nor Piping Engineer's Toolbox shows ads.

### Which is updated more often, HVAC Pipe Sizer or Piping Engineer's Toolbox?

HVAC Pipe Sizer ships an update every 9 months, and Piping Engineer's Toolbox every 21 months. Most recently, HVAC Pipe Sizer was updated on November 6, 2026 and Piping Engineer's Toolbox on November 8, 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.*