DET practice hub is live in Phase 1
From the team behind PrepEx TOEFL

Duolingo English Test prep built for the adaptive test.

PrepEx has helped TOEFL students practice with Petra, instant feedback, and skill-specific score reports. We are bringing the same practice loop to the Duolingo English Test: short mixed tasks, speaking and writing production, listening and reading drills, and DET score-scale feedback.

50,000+ PrepEx students 4.75/5 satisfaction Built around the DET 10-160 score scale

PrepEx is not affiliated with Duolingo. Duolingo English Test is a trademark of Duolingo, Inc.

Petra AI coach
Petra for DET
PrepEx coaching adapted for timed speaking, concise writing, integrated comprehension, and test-day fluency.

Sample DET score profile

Overall125 / 160
Speaking120
Writing130
Speaking
Timed production
Writing
Short, clear answers
Listening
Dictation and response
Reading
Adaptive vocabulary
Adaptive focus Practice for mixed tasks instead of fixed sections only
AI feedback Score reports, coaching, and progress tracking
DET scoring 10-160 scale language with skill-level feedback

Short tasks, clear feedback, steady repetition.

DET rewards fast, accurate communication across mixed skills. The first PrepEx DET practice hub focuses on the task families that benefit most from repetition and feedback: speaking production, writing production, dictation, vocabulary, and integrated comprehension.

Speaking

Practice photo description, read-then-speak, interactive speaking, and speaking sample style prompts.

  • Timed recording flow
  • Pronunciation and fluency notes
  • Answer structure coaching

Writing

Build concise written answers for production tasks where clarity matters more than length.

  • Writing sample practice
  • Grammar and vocabulary feedback
  • Response completeness checks

Listening

Train the audio tasks that require quick processing, accurate spelling, and strong memory.

  • Listen and type drills
  • Listen and select practice
  • Review after each attempt

Reading

Practice word recognition, sentence completion, and integrated reading tasks with instant review.

  • Read and select tasks
  • Fill in the blanks
  • Interactive reading prep

DET practice on proven building blocks.

PrepEx started with TOEFL, then expanded to IELTS, PTE, and CELPIP. DET will use the same foundation where it helps students most: authenticated practice, AI grading, score reports, progress tracking, and Petra coaching.

Trusted TOEFL foundation

PrepEx's TOEFL platform is used by thousands of students for timed practice, AI feedback, and section-by-section improvement.

DET-specific score language

Feedback will use DET score-scale language and skill categories instead of TOEFL scores or IELTS bands.

Built for mixed skills

DET practice will not force everything into traditional sections. The hub can support short tasks and integrated skill practice.

Students trust PrepEx for real score gains.

DET is new on PrepEx, but the platform behind it already helps students improve with AI grading, Petra coaching, and focused practice.

Student testimonials submitted via email

"I went from 81 to 106 in two months. The AI grading pointed out things I didn't even realize I was doing wrong. Petra helped me stop memorizing and just sound more natural."

Anastasia Kolokoltseva
Anastasia Kolokoltseva
Grad school applicant
TOEFL 81 to 106

"I think what helped most was just being able to practice as much as I needed. After a while I could see the same mistakes coming up less, and I went into test day a lot calmer."

Leyla Cetin
MBA candidate
TOEFL 95 to 112

"Speaking was the section I dreaded most. I kept freezing at the start of my answers, so doing that many practice questions was what finally made it feel normal."

Ryan Gunawan
Ryan Gunawan
Engineering student
TOEFL Speaking 13 to 23

Advised by language experts

Industry leaders guiding PrepEx's development across TOEFL, IELTS, PTE, CELPIP, and DET.

Meet our advisors

Start with the DET practice hub.

The first DET practice hub now supports starter content, progress tracking, objective grading, and saved writing or speaking responses. Tell us which DET score target you are working toward as the library expands.

DET billing and AI scoring remain disabled while the starter library and task players expand.