Get ready for your CPO exam.
CPO Pool Prep is your complete study companion for the Certified Pool Operator exam (PHTA): 300 exam-style practice questions across all 7 CPO topics, an official-format mock exam, and a detailed explanation for every answer, so you walk in ready.
Free to try · No subscription. No ads. One payment. · No account
Everything you need to pass. Nothing you don't.
One calm app for the whole CPO exam. Real exam conditions, every topic covered, and a detailed explanation whenever you need one.
All 7 CPO topics
Pool Calculations, Water Chemistry, Circulation, Filtration & Hydraulics, Safety, Health & Regulations, Disinfection & Water Balance, Spa & Hot Tub, and Maintenance & Seasonal Care: 300 exam-style practice questions, each with a detailed explanation.
Practice topic by topic
Short, focused quizzes that fit anywhere in your day. Every answer comes with instant feedback and a detailed explanation.
Official-format mock exam
50 questions in 90 minutes, 74% to pass (37 out of 50), the same 50-question format and pass mark as the real CPO certification exam. One free mock exam per topic to get started.
Pool calculations, drilled
75 calculation questions on pool volume, flow and chemical dosing, the questions that decide the real exam, practised until they become routine.
Review your mistakes
After every quiz, go back over what you missed and why. Your progress is tracked topic by topic, so weak spots don't stay weak.
One purchase, yours forever
No subscription, no ads, no expiring trial. Unlock the complete question bank and unlimited mock exams once, and keep them forever.
Three steps. Zero learning curve.
No account, no setup wizard that never ends. Open the app and start studying.
Pick an exam topic
Pool Calculations, Water Chemistry, Safety, Health & Regulations, Spa & Hot Tub and more. Start where you feel weakest.
Practice question by question
Short quizzes with a detailed explanation after every answer. 10 questions per topic are free, 70 in total across the 7 topics.
Sit the mock exam
50 questions, 90 minutes, 74% to pass, in the official format. One mock exam per topic is free, drawn from the free questions. When you pass here, you're ready for the real thing.
Free to try. One payment to own.
No subscription. No ads. One payment.
CPO Pool Prep Free
Start today — no account, no card.
- ✓ All 7 CPO topics
- ✓ 70 practice questions (10 per topic)
- ✓ 1 free mock exam per topic
- ✓ Detailed explanation after every answer
- ✓ Progress tracking and mistake review
- ✓ No ads, no account needed
- ✕ Complete 300-question bank
- ✕ Unlimited mock exams
CPO Pool Prep Pro
One-time purchase — no subscription.
- ✓ All 7 CPO topics
- ✓ Complete question bank: 300 questions
- ✓ Unlimited official-format mock exams
- ✓ Detailed explanation after every answer
- ✓ Progress tracking and mistake review
- ✓ No ads, no account needed
- ✓ Pay once — yours forever, no subscription
Your studying stays on your phone.
CPO Pool Prep was built for future certified pool operators. It treats your data the way it treats you: with respect.
- ✓No account, no sign-up. CPO Pool Prep never asks for your name, email, or any identifier.
- ✓Progress stays on your device. Your scores and history are stored locally on your phone and are never uploaded or shared.
- ✓No ads, no trackers. Nothing follows your studying, and there is nothing to sell.
- ✓Purchases handled by the stores. Pro is verified through RevenueCat with an anonymous identifier. We never see or store your payment information.
Read the full policy: engysgroup.com/cpo/privacy