# HVAC ToolKit vs cFormula

The clearest difference is price: cFormula at Free against HVAC ToolKit's $9.99. HVAC ToolKit's advantage is in-app purchases (none vs 1) and ads (none vs shown). On update cadence, device support and iOS requirement there is nothing between them.

cFormula is free to download; HVAC ToolKit costs $9.99 up front. cFormula sells 1 one-off in-app purchase. HVAC ToolKit asks for nothing beyond the download.

HVAC ToolKit ships an update every 3 months, cFormula every 5 months. The most recent releases landed on September 8, 2026 and August 25, 2026 respectively.

## The numbers

| Metric | HVAC ToolKit | cFormula |
| --- | --- | --- |
| Price | $9.99 | **Free** |
| Rating | **[1.0 (1 ratings)](https://appshunter.io/ios/app/hvac-toolkit/id1623246775/reviews)** | — |
| Number of ratings | **1** | — |
| In-app purchases | **No** | Yes |
| Ads | **No** | Yes |
| Update frequency | **Every 3 months** | Every 5 months |
| Monetization | Paid | — |
| Size | 60 MB | 13 MB |
| Requires iOS | **12.0** | 13.0 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Mohamad Jaber](https://appshunter.io/developer/1623246777) | [疆 边](https://appshunter.io/developer/1124320934) |

## What reviewers say

### HVAC ToolKit

[App page](https://appshunter.io/ios/app/hvac-toolkit/id1623246775)

This application provides HVAC engineers with tools for design checks and quick calculations. It offers various calculators for ducting friction, pipe sizing, ventilation, and heat load estimations, with clear instructions and formulas. Users can switch between metric and imperial units, and English or Arabic languages.

**Highlights:** Friction loss calculations, Pipe sizing tools, Ventilation and pressurization calculators, Heat load and pump head estimations, Metric/Imperial unit support, English/Arabic language options

**Features:** macOS Compatibility

**In-app purchases:** none


### cFormula

[App page](https://appshunter.io/ios/app/cformula/id6475750528)

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Fully unlock app | $1.99 | one-time |


## Frequently asked questions

### Is HVAC ToolKit free?

HVAC ToolKit costs $9.99, with no in-app purchases.

### Is cFormula free?

cFormula is free to download, with in-app purchases available.

### Do HVAC ToolKit or cFormula have ads?

cFormula shows ads; HVAC ToolKit does not.

### Which is updated more often, HVAC ToolKit or cFormula?

HVAC ToolKit ships an update every 3 months, and cFormula every 5 months. Most recently, HVAC ToolKit was updated on September 8, 2026 and cFormula on August 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.*