# AC Calculator vs EPA 609 Certification Prep

The clearest difference is in-app purchases: EPA 609 Certification Prep at none against AC Calculator's 2. EPA 609 Certification Prep also leads on update cadence (every 2 weeks vs every 4 months). AC Calculator's advantage is ratings volume (20 vs 4). On price, rating, ads and monetization model there is nothing between them.

Both are free to download. AC Calculator sells 2 one-off in-app purchases. EPA 609 Certification Prep asks for nothing beyond the download.

On the App Store both sit at effectively the same score — 4.8 for AC Calculator against 4.8 for EPA 609 Certification Prep. That said, the two scores are not equally well evidenced: AC Calculator has 20 ratings behind it against 4, so its average is the more settled of the two.

AC Calculator ships an update every 4 months, EPA 609 Certification Prep every 2 weeks. The most recent releases landed on October 18, 2026 and October 31, 2026 respectively.

## The numbers

| Metric | AC Calculator | EPA 609 Certification Prep |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.8 (20 ratings)](https://appshunter.io/ios/app/ac-calculator-hvac-sizing/id1537174761/reviews)** | [4.8 (4 ratings)](https://appshunter.io/ios/app/epa-609-certification-prep/id6762544342/reviews) |
| Number of ratings | **20** | 4 |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | Every 4 months | **Every 2 weeks** |
| Monetization | Free with in-app purchases | Free with in-app purchases |
| Size | 9 MB | 2 MB |
| Requires iOS | 18.6 | **17.0** |
| Devices | iPhone, iPad | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Melchisedec Martinez Rodriguez](https://appshunter.io/developer/1534398511) | [Shanghai Sheyuan Network Technology Co., Ltd.](https://appshunter.io/developer/1560626858) |

## What reviewers say

### AC Calculator

[App page](https://appshunter.io/ios/app/ac-calculator-hvac-sizing/id1537174761)

This utility app simplifies HVAC sizing by calculating BTU/h capacity and recommending equipment. It offers unit conversions, price estimates, and energy consumption comparisons. Advanced features can be unlocked via in-app purchases.

**Highlights:** Calculate BTU/h capacity, Recommend equipment types, Convert BTU, kW, Kcal, Tons, Check price estimates, Compare inverter vs. conventional

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

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Unlock View details | $4.99 | one-time |
| Unlock Advanced mode | $9.99 | one-time |


### EPA 609 Certification Prep

[App page](https://appshunter.io/ios/app/epa-609-certification-prep/id6762544342)

Prepare for your EPA Section 609 MVAC certification with focused practice questions, clear explanations, and an offline reference library. Master regulations, refrigerant identification, and safety protocols for the motor-vehicle air-conditioning exam.

**Highlights:** Practice mode with 50 multiple-choice questions, Explanations and citations for every answer, Mock exams mirroring the real certification test, Offline reference library for refrigerants and regulations, Diagnostic pass/fail analysis against EPA cutoff, One-time unlock for Pro content

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

**In-app purchases:** none


## Frequently asked questions

### Is AC Calculator free?

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

### Is EPA 609 Certification Prep free?

EPA 609 Certification Prep is free to download, with no in-app purchases.

### Which has better reviews, AC Calculator or EPA 609 Certification Prep?

AC Calculator is rated higher. AC Calculator averages 4.8 out of 5 from 20 ratings, while EPA 609 Certification Prep averages 4.8 from 4 ratings.

### Do AC Calculator or EPA 609 Certification Prep have ads?

Neither AC Calculator nor EPA 609 Certification Prep shows ads.

### Which is updated more often, AC Calculator or EPA 609 Certification Prep?

AC Calculator ships an update every 4 months, and EPA 609 Certification Prep every 2 weeks. Most recently, AC Calculator was updated on October 18, 2026 and EPA 609 Certification Prep on October 31, 2026.

---

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