# Caleffi Pipe Sizer vs Si

The clearest difference is review sentiment: Caleffi Pipe Sizer at 50% against Si's 0%. Caleffi Pipe Sizer also leads on rating (5.0 vs 3.0). On price, ratings volume, update cadence and ads there is nothing between them.

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

Caleffi Pipe Sizer holds the better App Store score, 5.0 against 3.0. Both are backed by a comparable volume of ratings — 1 and 1 respectively. Written reviews point the same way: 50% of Caleffi Pipe Sizer's written reviews are positive against 0% of Si's.

Caleffi Pipe Sizer ships an update every 7 months, Si every 6 months. The most recent releases landed on October 18, 2026 and October 22, 2026 respectively.

## The numbers

| Metric | Caleffi Pipe Sizer | Si |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[5.0 (1 ratings)](https://appshunter.io/ios/app/caleffi-pipe-sizer/id1088928458/reviews)** | [3.0 (1 ratings)](https://appshunter.io/ios/app/si-hvacr-measurement-mobileapp/id1475739979/reviews) |
| Number of ratings | 1 | 1 |
| Positive reviews | **50.0% of reviews** | 0.0% of reviews |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 7 months | **Every 6 months** |
| Monetization | Free | Free |
| Size | 44 MB | 55 MB |
| Requires iOS | 13.0 | **12.4** |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Caleffi S.p.A](https://appshunter.io/developer/920722440) | [SAUERMANN INDUSTRIE](https://appshunter.io/developer/1169513729) |

## What reviewers say

### Caleffi Pipe Sizer

[App page](https://appshunter.io/ios/app/caleffi-pipe-sizer/id1088928458)

This application assists hydraulic and HVAC professionals in accurately sizing water or air pipes. It calculates pressure drops and offers a modern, intuitive interface for precise system design on the go.

**Highlights:** Accurate water/air pipe sizing, Pressure drop calculation, Customizable technical parameter calculations, Extensive material and configuration library, Modern and intuitive interface, Enhanced performance

**Features:** macOS Compatibility

**In-app purchases:** none


### Si

[App page](https://appshunter.io/ios/app/si-hvacr-measurement-mobileapp/id1475739979)

This application connects to specific Sauermann instruments to display real-time measurement data on your smartphone. It allows you to manage, save, and export measurement datasets in various formats, including PDF, CSV, and XML.

**Highlights:** Real-time measurement display, Data management, Report generation, Export to PDF, CSV, XML, Bluetooth connectivity, Measurement of temperature, humidity, pressure, air velocity

**In-app purchases:** none


## Frequently asked questions

### Is Caleffi Pipe Sizer free?

Caleffi Pipe Sizer is free to download, with no in-app purchases.

### Is Si free?

Si is free to download, with no in-app purchases.

### Which has better reviews, Caleffi Pipe Sizer or Si?

Caleffi Pipe Sizer is rated higher. Caleffi Pipe Sizer averages 5.0 out of 5 from 1 ratings, while Si averages 3.0 from 1 ratings.

### Do Caleffi Pipe Sizer or Si have ads?

Neither Caleffi Pipe Sizer nor Si shows ads.

### Which is updated more often, Caleffi Pipe Sizer or Si?

Caleffi Pipe Sizer ships an update every 7 months, and Si every 6 months. Most recently, Caleffi Pipe Sizer was updated on October 18, 2026 and Si on October 22, 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.*