CEM® exam prep · coming soon

Practice the calculations, not just the terms.

A study app for the CEM® exam, on your phone and computer. Work through calculation-focused questions, see every step of the solution, and drill the formulas with new numbers until they feel easy.

Tell me when it launches Try 3 questions

Send us a short email and we'll write back when the app is ready.

A calculation question where every wrong answer shows the mistake behind it

1,041practice questions

2 × 130questions in two 4-hour practice exams

234calculation types with new numbers every time

1,303term and formula cards

Try 3 questions

The same questions and explanations as in the app. Options shuffle every time.

Built for a calculation-heavy exam

Formula calculator

Open it from any calculation question. Fill in what you know, leave one box empty, and it solves for that value, the result or any input.

Endless calculation drill

234 calculation types come back with new numbers every time, so you learn the method instead of remembering an answer.

Every mistake named

Each wrong option shows the slip that leads to it, such as a wrong unit or a missed step, and answers come with a step-by-step solution.

IP or SI units

Study in US units (°F, Btu, ft²) or SI units (°C, kW, m²). Formulas, worked examples and notes follow your choice.

4-hour practice exam mode

130 questions in 240 minutes, with flags, a question map and results by domain. The app calculator is hidden, so you practice with your own.

Notes with diagrams

Short notes for 26 chapters with formula boxes and 24 original diagrams. Questions stay in English like the exam; explanations in English, Korean or Spanish.

Formula calculator solving for one value — Formula calculator

Notes with a formula box — Notes and formulas

Practice exam with a 240-minute timer — 4-hour practice exam

Pictures for the hard parts

24 original diagrams inside the notes show how the numbers connect.

Air processes on a psychrometric chart — Psychrometric processes

Pump curve and system curve — Pump and system curves

Written for the exam topics

Our original questions cover all 14 domains of the published CEM Body of Knowledge. Practice exams follow the domain weights, and about 4 in 10 of their questions are calculations, so you can practice your pace with a real calculator.

No leaked questions (dumps). Every calculation answer is checked against its formula.

Simple pricing. No subscription.

30-day pass

For a short, focused month before your exam.

$19.99one payment

Full CEM access

Until the exam topics (BoK 1.8) change, at least 12 months. Best value.

$49.99

Both plans include:

1,041 practice questions with an explanation for every option
Two 130-question practice exams and random mock exams
Formula calculator and an endless calculation drill (234 types)
1,303 term and formula cards and notes for 26 chapters with 24 diagrams
IP or SI units · English, Korean and Spanish · works offline
Log in on your phone and computer; your progress syncs

Buying opens soon. Leave your email above and we will tell you first.

Free trial: 50 questions, 100 cards, chapter 1 notes and a 20-question mini mock.

For BoK 1.8; a future version is not included. No auto-renewal. Full refund within 7 days. Prices in USD; taxes may be added at checkout.

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Questions or ideas?

Email us any time. Language requests are welcome too.

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