# Phymetrix Calculator vs Instrument Toolbox

The clearest difference is price: Phymetrix Calculator at Free against Instrument Toolbox's $1.99. Instrument Toolbox's advantage is update cadence (weekly vs every 52 months). On review sentiment, ads, in-app purchases and device support there is nothing between them.

Phymetrix Calculator is free to download; Instrument Toolbox costs $1.99 up front. Neither carries in-app purchases, so what you see is what you pay.

Phymetrix Calculator ships an update every 52 months, Instrument Toolbox weekly. The most recent releases landed on October 6, 2026 and October 9, 2026 respectively.

## The numbers

| Metric | Phymetrix Calculator | Instrument Toolbox |
| --- | --- | --- |
| Price | **Free** | $1.99 |
| Rating | **[5.0 (2 ratings)](https://appshunter.io/ios/app/phymetrix-calculator/id1073762645/reviews)** | — |
| Number of ratings | **2** | — |
| Positive reviews | 100.0% of reviews | 100.0% of reviews |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 52 months | **Weekly** |
| Monetization | **Free** | Paid |
| Size | 1 MB | 8 MB |
| Requires iOS | 14.0 | **13.0** |
| Devices | iPhone, iPod | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [Alexander Bedrossian](https://appshunter.io/developer/674267968) | [立娜 王](https://appshunter.io/developer/1761096632) |

## What reviewers say

### Phymetrix Calculator

[App page](https://appshunter.io/ios/app/phymetrix-calculator/id1073762645)

This utility app simplifies moisture calculations by converting between various units and determining dew points and partial water vapor pressures. It's pre-programmed with essential scientific equations for common gases, making complex calculations straightforward.

**Highlights:** Moisture unit conversion, Dew point calculation, Partial water vapor pressure calculation, Pre-programmed scientific equations, Supports common gases, User-friendly interface

**Features:** macOS Compatibility

**In-app purchases:** none


### Instrument Toolbox

[App page](https://appshunter.io/ios/app/instrument-toolbox/id6698856248)

A professional calculator designed for industrial control, automation, and instrumentation engineers. It offers quick conversions and calculations for gas concentration, units, steam properties, flange levels, and pipeline flow. Ideal for both field debugging and engineering design.

**Highlights:** PPM to mg/m³ conversion with compensation, Industrial unit conversion (pressure, volume, temp, etc.), Saturated steam pressure and density calculator, Flange level migration calculations, Pipeline flow and velocity calculator, Real-time calculation results

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

**In-app purchases:** none


## Frequently asked questions

### Is Phymetrix Calculator free?

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

### Is Instrument Toolbox free?

Instrument Toolbox costs $1.99, with no in-app purchases.

### Do Phymetrix Calculator or Instrument Toolbox have ads?

Neither Phymetrix Calculator nor Instrument Toolbox shows ads.

### Which is updated more often, Phymetrix Calculator or Instrument Toolbox?

Phymetrix Calculator ships an update every 52 months, and Instrument Toolbox weekly. Most recently, Phymetrix Calculator was updated on October 6, 2026 and Instrument Toolbox on October 9, 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.*