Comparison

AC Calculator vs EPA 609 Certification Prep

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

AC Calculator

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
Read full description

AC Calculator makes HVAC sizing simple. Quickly calculate BTU/h capacity, get recommended equipment types, convert between BTU, kW, Kcal and Tons, check up-to-date price estimates, and compare inverter vs. conventional energy consumption. Unlock professional-grade features anytime with in-app purchases.

About

EPA 609 Certification Prep

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
Read full description

Preparing for your EPA Section 609 MVAC certification? EPA 609 Certification Prep gives you focused practice for the 25-question, open-book motor-vehicle air-conditioning exam — with clear explanations, CFR and SAE citations, and an offline reference library built for the shop. WHAT'S INCLUDED: Practice Mode - 50 multiple-choice questions covering Section 609 regulations, refrigerant identification, recovery equipment, leak detection, evacuation, retrofits, and hybrid / EV high-voltage safety. - Every answer paired with an explanation and a regulation or SAE citation (40 CFR Part 82 Subpart B, SAE J2788 / J2843 / J2851, and more). - Drill Core 609 topics or MVAC topics separately, or sweep across the whole bank. Mock Exams - Mock 1 — 25 questions, open-book format matching the real Section 609 exam. - Mock 2 — advanced MVAC scenarios: R-1234yf A2L handling, POE oil on hybrid compressors, retrofit compliance, evacuation to 500 microns. - Question overview grid + flag-for-review during the exam. - Section-by-section pass / fail diagnostic against the 84% EPA cutoff. Reference Library (always free) - Refrigerants: R-12, R-134a, R-1234yf, R-744, R-152a — with ODP, GWP, ASHRAE safety class, and service-port quick-reference. - Regulations: Section 609, Clean Air Act, Montreal Protocol, SNAP program, AIM Act. - Recovery Equipment: SAE J2788 / J2810 / J2843 / J2851 / J2845 standards plus the full MVAC service sequence. - Leak Detection: SAE J2791 / J2913 detector standards, common MVAC leak points, repair philosophy. - Safety: refrigerant exposure limits, A2L / A2 flammability, hybrid / EV high-voltage service, PPE, first aid. WHO IS IT FOR: - Automotive technicians preparing for Section 609 MVAC certification - Dealership service advisors needing refrigerant-handling authority - Vocational students and automotive-trade instructors - Independent mechanics servicing R-134a and R-1234yf systems WHY TECHS LOVE IT: - Fully offline — works in the shop, on the lot, or at a roadside service. - No ads, no tracking, no subscription traps. - Real citations on every answer so you can verify the source. - Completely free — every question, both mock exams, and the full reference library. No purchase, no account. - Clean UI designed for one-handed use on a phone next to the car. 100% FREE: Every practice question, both mock exams, and the full reference library are completely free — no in-app purchases, no subscription, no ads, no account. Practice questions are modeled on the Section 609 certification exam and the public 40 CFR Part 82 Subpart B regulations. This app is a study aid; certification is awarded by an EPA-approved 609 test administrator. Download EPA 609 Certification Prep and master the MVAC exam in your pocket.

Screenshots

AC Calculator4 screens
EPA 609 Certification Prep4 screens

Verdict

The call

The clearest difference is update cadence: EPA 609 Certification Prep at every 2 weeks against AC Calculator's every 4 months. AC Calculator's advantage is ratings volume (20 vs 4). On price, rating, ads and in-app purchases there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. AC Calculator sells 2 one-off in-app purchases and EPA 609 Certification Prep sells 1 one-off in-app purchase. Whichever you choose, the download price is not the number that matters.

ReceptionRating · Positive reviews · Number of ratings

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.

UpkeepUpdate frequency

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 24, 2026 respectively.

Scorecard2 real differences · 7 level
AC Calculator versus EPA 609 Certification Prep: the parameters behind the verdict, then further details
ParameterAC CalculatorEPA 609 Certification Prep
PriceFreeFree
Rating4.8 (20 ratings) — better4.8 (4 ratings)
Number of ratings20 — better4
Update frequencyEvery 4 monthsEvery 2 weeks — better
AdsNoNo
In-app purchasesYesYes
MonetizationFree with in-app purchasesFree with in-app purchases
DevicesiPhone, iPadiPhone, iPad
Requires iOS18.617.0 — better
Further details — not scored
Size9 MB2 MB
Age rating4+4+
DeveloperMelchisedec Martinez RodriguezShanghai Sheyuan Network Technology Co., Ltd.

Customer experience

AC Calculator

All ratings20 ratings
Positive95.0%
Neutral0.0%
Negative5.0%

EPA 609 Certification Prep

All ratings4 ratings
Positive100.0%
Neutral0.0%
Negative0.0%

In-app purchases

2 purchases

AC Calculator

One-time2
  • Unlock View details$4.99
  • Unlock Advanced mode$9.99
1 purchases

EPA 609 Certification Prep

One-time1
  • Unlock Full Certification Prep$9.99

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 in-app purchases available.
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 24, 2026.

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